[Derived from a patch by Ben Maurer]
* generator/Ctor.cs : generate code to detect subclassing and handle
GType registration and native object creation properly.
* generator/Parameters.cs : add PropertyName accessor for param attr.
* generator/Property.cs : use a new GLib.Value ctor.
* glib/ObjectManager.cs : redo hash access.
* glib/Object.cs : CreateNativeObject method to invoke g_object_newv
and some refactoring of RegisterGType and LookupGType.
* glib/Value.cs : make gtype field an IntPtr.
* glib/glue/object.c : glue for g_object_newv use.
* glib/glue/value.c : new glue for value creation.
* gtk/Dialog.custom : fix a ctor declaration for auto-reg.
* gtk/Gtk.metadata : mark a couple property_name attrs as examples.
* sample/Subclass.cs : use auto-GType-registration now.
svn path=/trunk/gtk-sharp/; revision=26916