adding GameState tests
adding GameState tests

dianwen/oogasalad_TowerDefense,codylieu/oogasalad_OOGALoompas,dennis-park/OOGALoompas,jordanly/oogasalad_OOGALoompas,sdh31/tower_defense,garysheng/tower-defense-game-engine,kevinkdo/oogasalad_OOGALoompas