In sql_load_notes, no longer adding offset clause if start = 0 since SQLite doesn't like offset without limit.
Switched from using "ilike" to "like" with lower(), since "ilike" is a PostgreSQL-specific extension.
Moved BACKEND flags from Database to Persistent to prevent need from circular imports (model files importing controller.Database).
* Revisions can be opened either in the current page or in a new window/tab.
* Added ability for a read-write notebook to contain read-only notes. This supports showing read-only revisions.
* Fixed updatedb.py to properly load the anonymous user.
* Updated initdb.py and updatedb.py to deadl with new-style /notebooks/notebookid?note_id=noteid wiki links.
* Made Persistent copy the revisions_list on each revision update so different revisions don't share lists.
* Prevented Note from updating its revision twice upon construction. Now it's only updated once.
* Work-around for nasty urlparse() caching bug related to unicode strings that cherrypy barfs on.
* Added optional revision flag to various controller.Notebooks methods to allow opening of a notebook with a particular note revision displayed.
* Made controller.Notebooks.save_note() return the newly minted revision timestamp upon a successful save.
* Whenever we get back a revision timestamp from save_note(), we store in in the client's list of revisions for that note.
* Now raising Access_error in controller.Notebooks in various places where the notebook requested is unknown.
* Tweaked pulldown CSS a bit. Now will sport a handy-dandy scrollbar if the pulldown gets too tall, at least in real browsers.
* Fixed bug where clicking "show on startup" checkbox directly didn't visually toggle the checkbox.