Set CMAKE_FIND_ROOT_PATH, use i686-w64-mingw32

The project now uses the MinGW headers instead of wine's headers.
install.sh: Download mingw from sourceforge.

It will automatically extract to /usr/local/
Extract with root privileges
Extract to subdirectory...
mkdir if it isn't present
Set the correct permissions after extracting.
Clean the code up (indentation)
Make toolchain compatible for both OSX and Linux
Merge pull request #358 from Balletie/master

Fix for blank screen at startup. (fixes #350)