Added minwidth resolutions

Noticed that the resolution was low on my computer, had a poke with getUserMedia stuff.

The results are good but I have no idea how it works, I don't understand why you can't ask for "max resolution pls", maybe you can help me figure this out. Obviously this is a hacky addition so I'd love to know what's going on :P

![screenshot from 2014-12-22 20 06 17](https://cloud.githubusercontent.com/assets/2445413/5530332/51ad1a9c-8a16-11e4-97a0-092bb72a762b.png)
After:
![screenshot from 2014-12-22 20 06 00](https://cloud.githubusercontent.com/assets/2445413/5530331/51a98846-8a16-11e4-8f0c-e40a203a4803.png)