0.9.4: Many cool new features

Version 0.9.4 saw the addition of nearly half a dozen gameplay features. A partial list:

-Pressing the wrong note now has audio feedback, via a random dissonant chord.

-You can still hear the song playing softly in the background even if you're screwing up, which helps you get back into the rhythm.

-In practice mode, you have more options. New additions:
-Hand isolation. You can now practice one hand at a time.
-Draw note names. If enabled, the name of each note (A, B, C#, etc.) is drawn under each circle. This should help you memorize the staff.
-Toggle hand positions. Lets you enable/disable the drawing of the hand position indicators.
-Note rendering method. In 'traditional' mode, the notes are drawn as black circles, with a sharp or flat icon in the middle. Combined with no hand positions drawn, and staff rotation set to always, you can simulate sheet music.