New: Window position (when in windowed mode) can be set from options.cfg

You know, it's really annoying that the game puts its window to different places every time i start it. (many times it lolls out of the screen)
Of course this problem is only existent in Windowed mode..
Now we can set the position of the window with windowedModePositionX and windowedModePositionY in the options.cfg.

It's a shame we can't save the last position on the exit of the game.
(for that we need SDL_WINDOWEVENT_MOVED which only exists in SDL 2.0)