Only redraw objects that intersect with an invalid region.
Merge pull request #511 from claus/master

add /me to authors
Stub console.time if missing
Mo button fixes.
Merge pull request #512 from tobeytailor/buttons

Mo button fixes.
Merge pull request #509 from tobeytailor/rendering

Only redraw objects that intersect with an invalid region.
Adds more goodies for legacy browsers
Even more compliant button behaviour.
Merge pull request #515 from tobeytailor/buttons

Even more compliant button behaviour.