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.
(cherry picked from commit 16e14353b1)
4873. [doc] Grammars for named.conf included in the ARM are now
automatically generated by the configuration parser
itself. As a side effect of the work needed to
separate zone type grammars from each other, this
also makes checking of zone statements in
named-checkconf more correct and consistent.
[RT #36957]