mouse position issues with canvas

[adekto]

having a canvas offset will mess up mouse position

fix: https://github.com/adekto/loveJS

[Sheepolution]

Oh wow, this is the first time someone contributed to a project of mine.

Thanks for the fix! To be honest, I kinda stopped working on loveJS. If there was enough people asking for it, I might go back to it, but there are probably people who can do a way better job than I do regarding javascript.

Anyway, I think you need to make a pull request so that I can pull your commit into the official project.