* Remove duplicate backend columns
* Remove duplicate column routines
* Move columns on frontend from state to model
* Generate available columns from Colum enum
* Add second column label for notes mode
So, this is fun. Apparently "DeckId" is considered preferable to the
"DeckID" were were using until now, and the latest clippy will start
warning about it. We could of course disable the warning, but probably
better to bite the bullet and switch to the naming that's generally
considered best.