Merge pull request #4 from dotfloat/master

Fix "Version Date" in the title so it actually displays the date.
Correct video menu subtext
Add dotfloat, DavidPH to AUTHORS
SDL2 now works on MinGW-w64, FindSDL2 dos2unix'd

Also moved SDL_win32_main.c over to a new folder and fixed up both the
CMakeFiles.txt
Import savegame thumbnail crash fix(r1279-r1280)

r1280 | svkaiser | 2014-03-01 20:07:37 -0800 (Sat, 01 Mar 2014)

+ Don't try to do any stupid cropping for widescreen resolutions when
saving out thumbnails

r1279 | svkaiser | 2014-03-01 20:07:04 -0800 (Sat, 01 Mar 2014)

+ Avoid using memcpy in GL_GetScreenBuffer