Reworked COStore, COEditingContext, COPersistentRoot and COBranch to all support both 
short and detailed descriptions as advertised.


git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@10075 7b3f36aa-e6db-49c1-8b4c-66eac1997e64