Application: Pass 0 (NULL) rather than  to GApplication.

* gio/src/application.ccg: It is annoying that GApplication (and other
C code) distinguishes, of course.
Glib::add_exception_handler(): Fix misplaced endif.

* glib/glibmm/exceptionhandler.h: Fix a misplaced endif, which has made
Doxygen exclude add_exception_handler() from the documentation.
Thread::RecMutex: Don't initialize this as a GStaticMutex.

The previous code (removed here) depended on an implementation
detail of GStaticRecMutex, which was changed in this glib commit:
http://git.gnome.org/browse/glib/commit/?id=2b281e40f32b7916d856dcc95e6f8fe625fcff03

This change avoids a deadlock with that version of glib.
Note that Thread::* is deprecated anyway, which is lucky because we do not
know for sure that this fix is enough.
Bug #677291
Simplify the gen_scripts slightly.

	* tools/gen_scripts/gio_generate_docs.sh:
	* tools/gen_scripts/gio_generate_enums.sh:
	* tools/gen_scripts/gio_generate_methods.sh:
	* tools/gen_scripts/glib_generate_docs.sh:
	* tools/gen_scripts/glib_generate_enums.sh:
	* tools/gen_scripts/glib_generate_methods.sh:
	Do not require changes to PATH.
gen_scripts: Correct some comments/documentation.

	* tools/gen_scripts/gio_generate_extra_defs.sh:
	* tools/gen_scripts/glib_generate_extra_defs.sh:
	These do not need JHBUILD_SOURCES to be defined.
Update .gitignore.

* .gitignore: Add /glib/glibmm/threads.[h|cc]. Update /examples/dbus/*.
Glib::Checksum: Fix a typo.

* glib/src/checksum.hg: Should be *_SHOULD_*, not *_SHOUD_*.
2.32.1
ContentType: get_icon(): Fix a refcount error.

* gio/giomm/contenttype.cc: get_icon(): Take a reference.