Upgrade Idris 0.12 and SDL 1.2.15#12

Open

steshaw wants to merge 2 commits intoedwinb:masterfrom

Commits on Jul 22, 2016

Get working with SDL 1.2.15 & SDL_gfx 2.0.25 (WIP).
steshaw
committed

Commits on Jul 24, 2016

Updated effects. However, etest.idr now causes compiler to spin.
steshaw
committed