GtkContainer child properties
* generator/Property.cs:
* generator/ChildProperty.cs: make Property subclassable and add a
"ChildProperty" subclass.
* generator/Makefile.am (sources): add ChildProperty.cs
* generator/ClassBase.cs: handle "childprop" nodes by creating
ChildProperty objects.
* glib/Value.cs (explicit operator EnumWrapper): use
g_value_get_flags() rather than g_value_get_enum() when
appropriate.
* glib/glue/value.c (glibsharp_value_holds_flags): glue for that
* gtk/gtk-api.raw: regen to pick up child properties
* gtk/Gtk.metadata:
* gtk/Container.custom: hide the auto-generated
Gtk.Container.ChildGetProperty and implement a nicer one by hand.
* gtk/glue/container.c (gtksharp_container_child_get_property):
utility function to set up an appropriate GValue for us
svn path=/trunk/gtk-sharp/; revision=35702
