Implementado flyweight, mas encheu de BUG
Merge origin/master

Conflicts:
	SpaceInvaders/src/spaceinvaders/gameobjects/naves/Inimigo.java
	SpaceInvaders/src/spaceinvaders/gameobjects/naves/InimigoRosinha.java
	SpaceInvaders/src/spaceinvaders/gameobjects/naves/InimigoVerde.java
	SpaceInvaders/src/spaceinvaders/gameobjects/tiro/TiroInimigo.java