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

iMFC r303400: libcxxrt: fix demangling of wchar_t

'wchar_t' is 7 characters long, not 6. r303297 (MFC'd in r303398) fixed
this in libelftc, but not the second copy of this file that we have in
libcxxrt.

PR: 208661
Approved by: re (gjb)

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

Since contrib/libcxxrt's ancestry was never correct, subversion 1.8 and
higher cannot merge to it from the vendor area.

Re-bootstrap the ancestry by doing (apologies to your retinas):
* svn pg svn:mergeinfo contrib/libcxxrt > mergeinfo.txt
* svn rm contrib/libcxxrt
* svn cp ^/vendor/libcxxrt/dist@297299 contrib/libcxxrt
* svn rm CMakeLists.txt doxygen_config
* svn cp ^/head/contrib/libcxxrt/FREEBSD-upgrade@297299 contrib/libcxxrt
* svn cp ^/head/contrib/libcxxrt/exception.cc@297299 contrib/libcxxrt
* svn cp ^/head/contrib/libcxxrt/unwind-arm.h@297299 contrib/libcxxrt
* svn pd -R svn:mergeinfo contrib/libcxxrt
* svn ps -F mergeinfo.txt svn:mergeinfo contrib/libcxxrt

Import libcxxrt master e64e93fe5bba67a6d52cbe5a97f8770c054bfa65

This includes a number of fixes to the C++ demangler (obtained from
upstream ELF Tool Chain).

Imported newer libcxxrt into vendor branch.

Import libcxxrt / libc++ into a vendor branch.

Approved by: dim (mentor)