Merge pull request #6 from smathot/master

Nice! Kind of what I had in mind. Thanks!
updated event detection
import sys before using it

We forgot to import sys before using it.
import time before using it

And we should import time before using it too. Silly mistakes!
PyGameScreen.draw_image now accepts pygame.Surface and PIL images
Merge branch 'master' of https://github.com/esdalmaijer/PyGaze
new additional library for webcam interaction
updated libwebcam
libwebcam allows camera back-end choice and provides elaborate error messages
prevent pygame timeout disfunction

Since new PyGame timing, 0 ms does not do the trick anymore (timing was millisecond accurate, so could not see difference between 0 and a really short time below 1 ms). We now need a timeout of a bit over 0 ms to achieve the same effect.

PyGame timeout is at 0 ms, because (for some reason) it really slows down drawing when it's at 1 ms. Don't have a clue why, though...
Add utf-8 encoding header to source files and move version indication to module __init__.py.
Bump to 0.4.2~pre1