Tweaks to player BlackHole, PlayerCharacter

- Added black hole script to black hole prefab

-Unfortunately there is a weird bug with unity right now that (only
sometimes) when you place a black hole prefab, the sprites don't default
to center pivot. So you have to go to the art assets and individually
change the pivot to something else, back to center and then apply. Ew.

- Got rid of some rouge debugging statements

- Chnages some GameObject.find 's to class.instance where available