Started rewriting the README about the SDL 2.0
Started rewriting the README about the SDL 2.0

Should be broader about compiler support.

walls-of-doom/walls-of-doom,walls-of-doom/walls-of-doom,mafagafogigante/walls-of-doom,mafagafogigante/walls-of-doom,walls-of-doom/walls-of-doom,walls-of-doom/walls-of-doom,mafagafogigante/walls-of-doom