ruby: silence configure warning
libmatroska 1.4.1
mkvtoolnix: add deps on libebml and libmatroska

The mkvtoolnix release tarball contains vendored copies of both of these
libraries, but the build system will select an external copy if one is
installed. There are no knobs to control this behavior, so it is safer
to add the dependencies rather than allow opportunistic linking.
wine devel 1.7.7
swipl 6.6.0 and 7.1.0, install wrappers for all tools
ruby: add caveat about restoring gem binstubs
Remove libgsasl again

This reverts commit 84240f577ac49e6ef95dac7ff15c939d006649b9.
Fix MacOS::CLT.installed? for 10.9+

This continues to use mavericks_dev_tools? instead of trying to read
from pkgutil because pkgutil is really slow.

Fixes #24123.