Move user config location to XDG compliant directory.
Merge pull request #12 from soeb/master

Move user config location to XDG compliant directory. Thanks soeb!
Remove the need for OpenGL 4 and lots of small bugfixes
- Fix blend functions not being reverted.
- Fix GL_ELEMENT_ARRAY_BUFFER not being reverted.
- Fix keyboard event state handling.
- Add the ability of disabling key combos.
- Now works on OpenGL 3.
Increment version number