bitsy v7.3

Hey y'all, it's been a while, but I've got a little update with some bugfixes!  💙

Here are all the changes:

• save grid on/off settings between sessions
• bugfix: Samuel Fine fixed mobile touch controls
• bugfix: @seansleblanc fixed unrecoverable state from loc bug
• bugfix: extra newlines were added in dialog
• bugfix: return exit's "move" button wasn't localized
• bugfix: checkbox states were wrong on page load
• bugfix: room nav controls were broken after game data edits
• bugfix: stop deleting dialog that's still referenced

I managed to fix a few of the things that folks told me about in the comments on the "bitsy nuisances" blog post - so thank you everyone who gave suggestions! I'll try to fix more as I find time. :)