Updated Rooler

Just updated Rooler to add multi-mon support, by popular request :)

As a bonus feature I also added support for high-DPI monitors.

I should have had multi-mon in the first version, but got psyched out by it. Once I sat down to really get it fixed it only took an hour or so- always good when it goes like that. High DPI was a different story, I have my fingers crossed that I didn't break anything :)

Enjoy!