.gitignore: Ignore all .deps, .dirstamp
Fix crash when using GC_malloc_many() as first allocation call

* mallocx.c (GC_CALL GC_generic_malloc_many): Do not dereference
ok_reclaim_list if it is NULL.
Fix PARALLEL_MARK for Windows 7+
(Apply commit c2c650f from 'release-7_4' branch.)

* doc/README.macros (DONT_USE_SIGNALANDWAIT): Remove.
* win32_threads.c (DONT_USE_SIGNALANDWAIT, GC_mark_mutex_waitcnt,
SignalObjectAndWait_type, signalObjectAndWait_func): Likewise.
* win32_threads.c (GC_marker_cv, GC_mark_thread, start_mark_threads,
GC_mark_mutex_state, GC_acquire_mark_lock, GC_release_mark_lock,
GC_wait_marker, GC_notify_all_marker, GC_thr_init): Do not check
DONT_USE_SIGNALANDWAIT macro (assume it is always on as multi-core
marker based on NT SignalObjectAndWait is broken in Windows 7+ leading
to a deadlock sometimes because the function is no longer atomic).

Conflicts:

    win32_threads.c
Update ChangeLog
Update (regenerate) configure files

* Makefile.in: Regenerate.
* configure: Likewise.
* ltmain.sh: Likewise.
Regenerate configure files by new automake (v1.14.1), libtool (v2.4.2.418)

* Makefile.in: Regenerate (by autoreconf -vif using autoconf-2.69,
automake-1.14.1 and libtool-2.4.2.418).
* aclocal.m4: Likewise.
* config.guess: Likewise.
* config.sub: Likewise.
* configure: Likewise.
* include/private/config.h.in: Likewise.
* ltmain.sh: Likewise.
* m4/libtool.m4: Likewise.
* m4/ltoptions.m4: Likewise.
* m4/ltsugar.m4: Likewise.
* m4/ltversion.m4: Likewise.
* m4/lt~obsolete.m4: Likewise.
* missing: Likewise.
* test-driver: Likewise.