Cell and lattice coordinates, fixes #25

	modified:   cellular_automata/lattices/base.py
	modified:   cellular_automata/lattices/equiangular.py
	modified:   cellular_automata/lattices/neighborhoods.py
	modified:   cellular_automata/visualization/base.py
	modified:   experiments/game_of_life_test.py
Additional fix for issue #25

	modified:   cellular_automata/lattices/equiangular.py
	modified:   experiments/mlp_rule_test.py