Update the copyright information in all files in the repository

This commit converts the license handling to adhere to the REUSE
specification.  It specifically:

1. Adds used licnses to LICENSES/ directory

2. Add "isc" template for adding the copyright boilerplate

3. Changes all source files to include copyright and SPDX license
   header, this includes all the C sources, documentation, zone files,
   configuration files.  There are notes in the doc/dev/copyrights file
   on how to add correct headers to the new files.

4. Handle the rest that can't be modified via .reuse/dep5 file.  The
   binary (or otherwise unmodifiable) files could have license places
   next to them in <foo>.license file, but this would lead to cluttered
   repository and most of the files handled in the .reuse/dep5 file are
   system test files.

lib/isccc/alist.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/base64.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/cc.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/ccmsg.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/alist.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/base64.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/cc.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/ccmsg.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/events.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/sexpr.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/symtab.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/symtype.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/types.h

@@ -1,14 +1,18 @@
 /*
  * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
  *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
+ *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, you can obtain one at https://mozilla.org/MPL/2.0/.
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/include/isccc/util.h

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/sexpr.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above

lib/isccc/symtab.c

@@ -1,5 +1,7 @@
 /*
- * Portions Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0 AND ISC
  *
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -7,8 +9,10 @@
  *
  * See the COPYRIGHT file distributed with this work for additional
  * information regarding copyright ownership.
- *
- * Portions Copyright (C) 2001 Nominum, Inc.
+ */
+
+/*
+ * Copyright (C) 2001 Nominum, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above