FNA Code Style ./P* - R*

Flibitized.  Removed unnecessary parenthesis from commutative additions.
Format fixes.

This fixes the items Flibitijibibo noted, and a couple of whitespacing issues
that MonoDevelop slipped into the code.
FNA Code Style Cleanup
Fix bizarre tabbing in licensing.
Simplify operator overloads
Merge pull request #188 from 3vi1/monogame-sdl2

FNA Code Style ./I* - R*