Upgrade mousetrap

Mousetrap now supports overriding stop behavior instead of us having to
hack it (via Mousetrap.stopCallback).
Make escape blur inputs

This effectively makes a 'normal mode' feeling by allowing you to
always get out of the other modes.

Especially effective if you don't use a modifier key to prefix commands.
Fake an 'insert mode' by pressing 'i'

Really, it is just a user-requested way to stop actions from happening.