Configuration files

Do not merge - this is a preliminary PR for discussion.

As of now, incorporates Dolphin's INI code for a configuration system. So far, handles for input controls have been added, but they haven't been hooked yet into the parts of code that use them. 
Not sure I agree... can you name any other software called "citra"?
However, I could live with either "citra" or "citra-emu", depending on how we want to brand ourselves...