merge with dev
Added additional sound files and animations (x2)
Added an AnimationHandler to take care of animations

It's currently only used for when a tank dies.
Changed the name of updateAnimations
Removed the first explosive animation
Changed the firerate and sound of defaultturret
Added MAX_HEALTH, and getter to Shield
Added a life- and shieldbar
Added MAX_HEALTH and getter to AbstractTank
Implemented the life- and shieldbar
merge with Sound