Barrier Update

Added a visible barrier that allways is active. no further functionality
implemented.
BarrierPowerUp Update
BarrierPowerUp Update

added Activation and DeActivation methods and basic functionality in
stealing the crystal from other teams.
Added new Goal sprite
BarrierPowerUp Update

extended stealing and collision functionality. de crystal now gets
bumped away when colliding with barrier.
Update
BarrierPowerUp basics Done
Merge remote-tracking branch 'origin/master'

Conflicts:
	DVA306 Project/DVA306 Project/CollisionHandler.cs
	DVA306 Project/DVA306 Project/Crystal.cs
	DVA306 Project/DVA306 Project/DVA306 Project.csproj.Debug.cachefile
	DVA306 Project/DVA306 Project/Player.cs