Add collation version support to querylocale(3).

Add collation version support to querylocale(3).

Provide a way to ask for an opaque version string for a locale_t, so
that potential changes in sort order can be detected.  Similar to
ICU's ucol_getVersion() and Windows' GetNLSVersionEx(), this API is
intended to allow databases to detect when text order-based indexes
might need to be rebuilt.

The CLDR version is extracted from CLDR source data by the Makefile
under tools/tools/locale, written into the machine-generated Makefile
under shared/colldef, passed to localedef -V, and then written into
LC_COLLATE file headers.  The initial version is 34.0.
tools/tools/locale was recently updated to pull down 35.0, but the
output hasn't been committed under share/colldef yet, so that will
provide the first observable change when it happens.  Other versioning
schemes are possible in future, because the format is unspecified.

Reviewed by:	bapt, 0mp, kib, yuripv (albeit a long time ago)
Differential Revision:	https://reviews.freebsd.org/D17166