Remove the mastefile-format map option

As previously announced, this commit removes the masterfile-format
format 'map' from named, all the tools, the documentation and the
system tests.

bin/tests/system/checkconf/bad-masterfile-format-map.conf

@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("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 http://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+options {
+	port 5300;
+};
+
+zone example {
+	type secondary;
+	primaries { ::1; };
+	masterfile-format map;
+};