[armedbear-devel] Symbols moved into THREADS

[svn 12053][1] removes the Gate implementation, and moves more related symbols in THREADS.

[1]: http://trac.common-lisp.net/armedbear/changeset/12053

Move additional symbols into THREADS package.

The symbols

THREADP THREAD-UNLOCK THREAD-LOCK THREAD-NAME THREAD-ALIVE-P CURRENT-THREAD DESTROY-THREAD INTERRUPT-THREAD WITH-THREAD-LOCK MAKE-THREAD-LOCK MAKE-THREAD INTERRUPT-THREAD MAPCAR-THREADS GET-MUTEX MAKE-MUTEX WITH-MUTEX RELEASE-MUTEX

have been moved from EXTENSIONS into THREADS.

These primitives are still part of the EXTENSIONS package but are now