Fix oval and ngon. (It's PI, not pi!)
Merge branch 'dev' of https://github.com/evancz/Elm into dev
Fix move to have y-axis properly oriented.
Fix rotations (`degrees` and `turns` functions were broken because I used `Math.pi` instead of `Math.PI`...)
Change the name of `Keyboard` to `Keys`. Change some function names and change type of `charPressed` to be the latest char pressed (default is '\0')
Change names back to be longer but better.
Change type of toCode and fromCode
Add `groupTransform` function.

Add public Matrix library. Clean up and debug matrix implementation.
Merge remote-tracking branch 'origin/dev' into dev
Docs update: update Json from elm-lang.org docs
Docs update: update Graphics.Color Graphics.Text from elm-lang.org docs