Menu button fix

This leaves the native buttons alone, and adds ours in the same size and
style, at the bottom and just inside the native buttons.
Fixes for HC stats

Updated stats panel for Heavenly Chips and Cookies
Fix button highlighting

Our buttons now highlight when active and on hover
Clicking our buttons removes highlighting from other buttons
Merge pull request #119 from super-aardvark/buttons-fix

Menu button fix
use the bottom button background positions and align the borders
Merge pull request #120 from super-aardvark/heavenly-stats-fix

Fixes for HC stats