Added Dangerous Foraging Task

I went ahead and added a variant of Ken's old dangerous foraging task,
since it seemed like a task that involved two modes of behavior. Of
course, Ken was able to solve the task easily using plain NEAT, and sure
enough, HyperNEAT can also solve the task easily without needing
multiple brains or policies, so I haven't bothered testing out
multimodal networks in this domain. However, the process of adding this
domain did help me develop a robot that only has pie-slice sensors and
no range-finders. Perhaps a slightly harder variant of this domain could
require multimodal networks.