as "type primary" is preferred over "type master" now, it makes
sense to make "primaries" available as a synonym too.
added a correctness check to ensure "primaries" and "masters"
cannot both be used in the same zone.
The ARM and the manpages have been converted into Sphinx documentation
format.
Sphinx uses reStructuredText as its markup language, and many of its
strengths come from the power and straightforwardness of
reStructuredText and its parsing and translating suite, the Docutils.
The keyword 'unlimited' can be used instead of PT0S which means the
same but is more comprehensible for users.
Also fix some redundant "none" parameters in the kasp test.
- this required modification to the code that generates grammar text for
the documentation, because the "dnssec-lookaside" option spanned more
than one line in doc/misc/options, so grepping out only the lines
marked "// obsolete" didn't remove the whole option. this commit adds
an option to cfg_test to print named.conf clauses only if they don't
have the obsolete, ancient, test-only, or not-yet-implemented flags
set.