Added blend operations to Framebuffer.
Added blend operations to Framebuffer.

DerThorsten/magnum,ashimidashajia/magnum,MiUishadow/magnum,DerThorsten/magnum,MiUishadow/magnum,MiUishadow/magnum,DerThorsten/magnum,ashimidashajia/magnum,ashimidashajia/magnum,DerThorsten/magnum,ashimidashajia/magnum,MiUishadow/magnum,MiUishadow/magnum,DerThorsten/magnum,ashimidashajia/magnum,MiUishadow/magnum