FFI now supports callbacks to Haskell (albeit only functions without parameters for now).

Remove obsolete 'callDeferredFunction' function.
Add canvas functions `fillRect` and `setFillStyle`
Add example that uses the new canvas functions.
Add the function `setStrokeStyle`, `beginPath`, `moveTo`, `lineTo`, `closePath`, `arc`, `arcAC`, `fill`, `stroke` to the canvas module.
Update CanvasExample to use the newly added functions
Add function `setLineWidth`
Merge branch 'origin/master'
Converted to FP Complete Haskell Center
Fix CPP to work with plain ghci.
First stab at adapting to FPComplete IDE
Library compiles with FPComplete IDE.
Chat example can now be deployed with FPComplete IDE. Websocket communication doesn't work, though.
Change default port number to 8023. #64

Read port number from environment variable PORT if available.
Merge branch 'origin/develop'

Conflicts:
	samples/Chat.hs
Merge branch 'origin/fpcomplete'
Merge branch 'origin/master'

Conflicts:
	CHANGELOG.md
	threepenny-gui.cabal
Update CanvasExample.hs
Use `Double`s for radians in `arc` and `arcAC`
Fix CanvasExample.hs to use Doubles for `arc`
Merge 'upstream/master' into canvas