* components/adapter/nautilus-adapter-factory-server.h,
	components/adapter/nautilus-adapter-factory-server.c:
	(nautilus_adapter_factory_server_initialize,
	nautilus_adapter_factory_server_destroy): minor cleanups
	(impl_Nautilus_ComponentAdapterFactory_create_adapter): Actually
	create some objects.
	(adapter_object_destroyed): Watch for object destruction, for
	factory lifecycle management purposes.

	* components/adapter/nautilus-adapter.h,
	components/adapter/nautilus-adapter.c: Initial implementation of
	class that does the actual adapting. For now, it only handles
	Embeddables that take input via PersistStream. Later I will apply
	the Strategy pattern to virtualize visual embedding (Control
	vs. Embeddable) and loading (PersistStream vs. PersistFile
	vs. ProgressiveDataSink) (and fix some missing bits in the
	embedding virtualization).

	* components/adapter/Makefile.am: Build the new files.