Debugging: add convenience methods to CORevision, COPersistentRoot, COBranch to open graphviz pdf's

git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@10025 7b3f36aa-e6db-49c1-8b4c-66eac1997e64
Add -description to COAttributedStringDiff and the edit classes

git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@10026 7b3f36aa-e6db-49c1-8b4c-66eac1997e64
Synchronizer: forgot to migrate to CODiffManager. this fixes the 'hello' bold+underline merging issue

git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@10027 7b3f36aa-e6db-49c1-8b4c-66eac1997e64