small documentation update
[#600] ensure the given parameter is valid before parsing it

That needs further debug to see why this is happening only with
Canvas+, but I do not have an android device (for debugging) now, and
can only cure the symptom and not the cause ….
Merge branch '2.0.x'
[#608] added a private `globalColor' object in the canvas renderer to cache the current global color

this properly fixes the issue with cocoonjs/canvas+ where the
`fillStyle` property is undefined, by using this `globalColor` property
for the `setColor` function.
this also matches the webGL renderer implementation !
[#608] added parameter check for both parseRGB and parseHex and not throw an exception if the given arguments are not valid
Merge remote-tracking branch 'origin/2.0.x'
Normalize whitespace.
Normalize whitespace.
Cleanup `onend` callback in me.audio.play()
Update ChangeLog
Don't create a new function if a callback is not needed.
merged into master
Merge branch 'master' of https://github.com/melonjs/melonJS
better docs on spritewidth
version bumped to 2.0.2 !
updated to the latest Howler 2.0 build

the previous audio loop fix is not part of the official build
better docs on spritewidth
sync'ed with 2.0.x
reverted the last changes on the `globalAlpha` function
Merge remote-tracking branch 'origin/2.0.x'