games/stonesoup, games/stonesoup-sdl: update to 0.20.0

This release is filled with cool new stuff. Read about it here:
http://crawl.develz.org/wordpress/crawl-0-20-scarf-our-wanderful-fried-frogs

Port changes:
o switch to new master site layout and enable https://
o drop several now unnecessary local patches
o chase SOUND refactoring
o implement and enable sound support for SDL (tiles) option unconditionally

• this uses SDL_mixer and not /usr/local/bin/play like the SOUND option