Only meant to be one set of ant IDs, not two.
Correctly work out the next direction
multistep the world; step for each ant still alive
Filenames & game iterations from command line args
Run game by unfolding the result of multistep.
Show food otherwise show the ant
print number of ants alive
Print the first world and last
foldl' instead of foldr
Put the correct ant in the updated world.

Ant was keeping food in its mouth and adding new food to the cell.
delete unused test world
Add script for running game
Update executable