Mobile support

[shazow]

Very close to playable on mobile, just the left side is cut off. Hopefully just a minor CSS issue.

Great game btw, really enjoyed it. :)

Edits:

• Looks like the transform on .center is what's breaking it.
• Unfortunately touch events aren't being captured yet either, hmmm.
• Ah probably just need to add touchstart and touchend events in addition to mousedown and mouseup.

[jmankopf]

Thank you for your feedback. Originally I had planned a mobile version, but the canvas scaling didn't work out as expected.

As soon as I have some time, I'll start the task.