More mouse hot spot stuff:

- User Defaults menu mousified
- When all hot spots have scrolled off the screen, clear the hot spot list
- Insert new hot spots in the front of the list so they will take precedence
  over any previously defined duplicate hot spots
- Numeric hot spot commands end in a carriage-return
- No auto-acceptence of numbers when there are keys in the keyboard buffer
- Baja UNGETKEY function now inserts keys into the "front" of the keyboard
  buffer (next to be consumed)
- Hot key @-code command text supports C-style escape sequences
  (allows encoding of ctrl chars, spaces, etc.)