GObject: turn add-property-after-init to a warning

We have turned up enough cases of this being done (including GTK API
allowing apps to do this to GtkSettings well after it has been
instantiated) that it is clear that we cannot really break this feature
while claiming to be backwards compatible.

For that reason, it becomes a warning rather than a critical (ie: it is
still well-defined behaviour, but you are discouraged from doing it).

The intention is to keep this feature for at least the next while.
A given GObjectClass will be able to avoid using GParamSpec pool for as
long as you don't install properties after init.  If you do that, you
will get a warning and we will devolve to using GParamSpecPool.

https://bugzilla.gnome.org/show_bug.cgi?id=698614
Updated Polish translation
Updated Czech translation
tests: Add a test for a specific invariant

See the documentation in the test. The invariant is used by
gnome-test-runner.

https://bugzilla.gnome.org/show_bug.cgi?id=701878
gmain: Document more use cases of g_main_context_wakeup()

https://bugzilla.gnome.org/show_bug.cgi?id=701878
updated kn translations
Updated Telugu Translations
docs: Fix g_binding_unbind() in the API reference
binding: Make unbind() release the reference on GBinding

The automatic memory management of GBinding is not optimal for high
order languages with garbage collectors semantics. If we leave the
binding instance inert but still referenced it will be leaked, so one
solution that does not throw away the baby of C convenience with the
bathwater of language bindability is to have unbind() perform an
implicit unref().

Hopefully, C developers will read the documentation and especially the
note that says that after calling unbind() the reference count on the
GBinding instance is decreased.

https://bugzilla.gnome.org/show_bug.cgi?id=698018
binding: Use hash table as a set
tests/binding: Ensure that the binding goes away

Use weak pointers so that we can check that the GBinding instance goes
away when it should.

https://bugzilla.gnome.org/show_bug.cgi?id=698018
Plug a small memory leak

g_test_trap_assertions was leaking the process_id string.
Try to make the testgdate test hobble along a little longer
2.37.2
Bump version
gobject/tests: Add missing build dependency
[l10n] Updated Italian translation.
g_uri_escape_string: Add missing allow-none annotation

https://bugzilla.gnome.org/show_bug.cgi?id=701409
g_uri_unescape_string: Mention (allow-none)/%NULL in documentation

https://bugzilla.gnome.org/show_bug.cgi?id=701409
Update Visual Studio Projects

Make all projects settings use the MultiByte character set when building
GLib to improve consistency.