* gtk/gtkbuilderprivate.h, gtk/gtkbuilder.h, gtk/gtkbuilderparser.c:
	Added support for parsing required toolkit versions (so that ui descriptions
	can target specific versions of the backend widget libraries) bug 527612.

	* gtk/docs/reference/gtk/tmpl/gtkbuilder.sgml: Added documentation
	for the added xml tags to the ui description.


svn path=/trunk/; revision=20152