Cellcharger update

* Cleaned up code
* Updated charging animations, blinks more nicely now.
![charging](https://cloud.githubusercontent.com/assets/2332094/2687757/995468aa-c26b-11e3-8e6a-16afd2267109.gif)

* ~~Added ability to emag cellcharger. This results in you "frying its heatsensor". Any cell left in the cellcharger after its fully charged will blow up (after roughly 30 seconds), breaking the charger (which will let you remove it with a welding tool) and destroying the cell.~~

~~The broken cellcharger sprite is horrible, I sprited it myself, please someone help me.~~