Added sound capabilities.
Merge branch 'master' of https://github.com/zebbedy/jcc2d
Merge branch 'master' of https://github.com/zebbedy/jcc2d
Testing larger tiles in BensTestWorld.h
Bugfix - sprites weren't dying.
Fixed bug with game exiting on calls to killCurrentWorld()
Added empty(), front(), and back() methods to SpriteGroups.
Cleaned up button stuff a bit, esp/ in TestWorld.h