contribs: added SDL, SDL_image, Freetype, libpng

Signed-off-by: Steven Noonan <steven@uplinklabs.net>

Created by  Steven Noonan  on October 15, 2009
SVBGY75CBM6CNB4WEMUPF37G7IFJCC3DPI532WKY7PQTY3YX7KNAC
Change contents