Typewriter: Fix bug where initially selected note gets deselected at startup. Call all text editing 'typing' in the undo history, for now

git-svn-id: http://svn.gna.org/svn/etoile/trunk/Etoile/Frameworks/CoreObject@10380 7b3f36aa-e6db-49c1-8b4c-66eac1997e64