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.
support for addzone/delzone feature (see change
#2930). Removed "new-zone-file" option, replaced
with "allow-new-zones (yes|no)". The new-zone-file
for each view is now created automatically, with
a filename generated from a hash of the view name.
It is no longer necessary to "include" the
new-zone-file in named.conf; this happens
automatically. Zones that were not added via
"rndc addzone" can no longer be removed with
"rndc delzone". [RT #19447]
