OAF/Bonobo stuff

[Havoc Pennington <hp redhat com>]

I have this basically done, with one big sticking point:
 gnome_moniker_find_in_naming_service()

Someone who understands the big picture should give me an idea what to
do with this function.

I have done the patch as follows:
 - bonobo-object-directory.h is an private, not-installed header 
   that abstracts OAF and GOAD functons. A configure option 
   --enable-oaf turns on OAF implementations, otherwise GOAD.
 - functions that took a goad_id argument now have an _oaf_id() 
   equivalent function.
 - libgnorba/gnorba.h does not get included by gnome-bonobo.h and is 
   not required by any of the headers
 - apps require one or the other so none of the tests or samples work 
   with OAF, they are conditionally excluded from the Makefile

If we can solve the name server thing I will send the patch for
approval.

Havoc