Implement bookmark class cluster using a separate placeholder subclass
Implement bookmark class cluster using a separate placeholder subclass

git-svn-id: 765db44a9620ed55f4f8addfd3c14fe8cd57f6bb@4423 0fceea05-a30d-0410-8a8b-80ef821fb0a1

nanoant/Skim,nanoant/Skim,nanoant/Skim,nanoant/Skim,nanoant/Skim