Merge pull request #21 from emtwo/parser-listeners

Parser listeners
Remove italics and change to sans-serif
adding antialiasing and fixing a few button bugs. adding back button and help button to score panels
Merge branch 'master' of https://github.com/emtwo/piano
Add colored backgrounds for the key menus
Merge branch 'master' of https://github.com/emtwo/piano
Change colors for the home screen and ear training sub menu
Changed HelpButton to use a textarea for writing out the help message.
More help button changes.
Create abstract class for ear training.
Keep score and streak.
Add AdvancedChordTraining.
Positioning.