UI Improvements: Auto-Notes and Mode Backgrounds

Hi folks,

As discussed in the last update, I've just uploaded a new build with a couple of UI improvements:

1. Autonotes: By default, the notes popup will now disable any numbers that a given tile cannot have based on its visible neighbors and the visible tiles in the same room. (However, the Auto-Notes system does not attempt to automate any of the reasoning that might allow you to eliminate numbers for more complex reasons.) When new tiles are revealed, the auto-notes system will also automatically remove any newly-forbidden numbers from your existing notes.
2. Mode backgrounds: Based on some feedback that it is sometimes too easy in the mobile interface to accidentally explore a tile when one intended to take notes, the color of the background clouds is now used to more loudly signal which mode of the mobile interface is currently active. In note-taking mode the background clouds will be now purple, and in explore mode they will be orange.

These new features can be disabled from the Options menu if they are not to your liking.