[basic] path finding added.

Monster now gets the distance between itself and the player, then gets a free adjacent square and checks the distance from that adjacent square, if the distance is less than the current square, they will move to that square.
also updated how the monster moves, because the boundary test exists within the adjacent rule, using adjacent never returns a coordinate that is outside the game world, so now the new coordinates are passed straight to the monster as their new coordinates.

also merge a commit that closes #6 .