Close #177 Renamed and public may need to live off of camera
Reorganize directory structure per suggestion in #207
Update bower and npm package
Update CONTRIBUTING.md
Close #100 collision grouping implemented
Closes #218 Added particle startSize and endSize to particle tester
resolving merge
added 'die' action

allows for an actor to be removed from the scene only after completing
the previous actions in its action queue
Merge pull request #231 from excaliburjs/dev-josh

added 'die' action