added possibility to change heuristic from config file

AI.conf

AI/src/game/config.cpp

AI/src/game/config.hpp

AI/src/game/test_penguin_game.cpp

AI/src/main/main.cpp

AI/src/mcts/penguin_heuristic.cpp

AI/src/mcts/penguin_heuristic.hpp

AI/src/mcts/test_mcts_two_players.hpp