adding support for gestureworks

[zxcvbad]

I've managed to run gestureworks with dolphin, it does start successfully when using x86 version of Dolphin. Unfortunately gestureworks virtual gamepad doesn't respond when pressing it. But I've found a video where the guy made it work on surface pro 2. There's no info what build he's using and what backend. I've tried number of builds myself and tried all the backends (D3D,Dx11, OpenGL) buttons are there, but nothing happens when pressing them. Here's a video of Dolphin + gestureworks on surface pro 2: http://youtu.be/RdWUC-dIXhQ