Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Posixify the locales name for variants

For all locales with variants:
- if no ambiguity on the locale (only one variant) just use the regular name
- if ambiguity, pick one as default and append @<variant> to the others
respecting POSIX

As a result:
- All the 3 components locales added recently are renamed to the usual 2
components version for all but sr_RS.UTF-8
- Set sr_RS.UTF-8 to the cyrillic variant
- Add sr_RS.UTF-8@latin
- Remove the symlinks aliases they were created to represent the 2 components
version as aliasas and are now useless
- Update the OptionalObsoleteFiles.inc and ObsoleteFiles.inc to reflect those
changes

Discussed with: ache@
Approved by: re@ (gjb)