- I think everything should default to resize now (much easier than having to figure that crap out)
- new mouse_get_pos_unscaled() function to return 1024x768/640x480 relative values so we don't have to do it later
- lots of little cleanups which fix several strange offset/size problems
- fix gr_resize/unsize_screen_pos() so that it won't wrap on int (took too long to track this down)