#19 Emulator plugins

[jlocke]

Thought of an awesome feature that would seriously improve user acceptance/usability. Create a plugin mechanism that allows users to automatically import and install supported emulators into GFuel. This will:
* Lower the barrier to entry significantly. Simply launch GFuel, and you can get up and running with an emulator, instead of finding and configuring one
* Optimize playing settings for the fullscreen setup. Since the emulators are known, we can specify the optimal params to use.
* Make it easy to get running with any system without having to chase down options.

Making this cross-platform, and especially cross-distro, could be hairy due to non-portability of Linux binaries. Maybe getting a Windows build working first would be a good idea.