Fixing the toggle buttons possibly being in a bad state when quitting
and restarting the ValenceActivity.
Fixing getting the proximity power timeout as a number.
Added a thread safe way to get the RFBThread's handler.
Removing the hint overlay from the TouchPadView.
Added showing key presses in the UI as it is being typed.

Moving key event listening to separate classes, one for sending key
presses and one for updating the UI with key press feedback.

fixes #4