Moves tests from being RSASHA1 based to RSASHA256 based where possible
and split out the remaining RSASHA1 based tests so that they are not
run on OS's that don't support RSASHA1.
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.
This commit adds code for generating keys with dnssec-keygen given
a specific dnssec-policy.
The dnssec-policy can be set with a new option '-k'. The '-l'
option can be used to set a configuration file that contains a
specific dnssec-policy.
Because the dnssec-policy dictates how the keys should look like,
many of the existing dnssec-keygen options cannot be used together
with '-k'.
If the dnssec-policy lists multiple keys, dnssec-keygen has now the
possibility to generate multiple keys at one run.
Add two tests for creating keys with '-k': One with the default
policy, one with multiple keys from the configuration.
