Changed ETLayoutItemGroup to turn inserted items into persistent objects if needed (and notify the editing context)
Changed ETLayoutItemGroup to turn inserted items into persistent objects if needed (and notify the editing context)

git-svn-id: 0833b781a6984bca00fd44c5b8a33a6c879c84c9@7113 7b3f36aa-e6db-49c1-8b4c-66eac1997e64

etoile/EtoileUI,etoile/EtoileUI