Added upgrade classes and units model
Merge remote-tracking branch 'origin/dev' into devUpgrades

Conflicts:
	TP3/src/ca/csf/RTS/game/Game.java
	TP3/src/ca/csf/RTS/game/Team.java
	TP3/src/ca/csf/RTS/game/entity/controllableEntity/building/WatchTower.java
	TP3/src/ca/csf/RTS/game/entity/controllableEntity/building/factory/Trainable.java
Merge pull request #81 from malmuki/devUpgrades

Dev upgrades