ETModelDescriptionRepository: Hack for GNUstep: create NSApplication before we initialize all loaded classes when building the model description repository.

git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/EtoileFoundation@10476 7b3f36aa-e6db-49c1-8b4c-66eac1997e64