new item: slime in a bucket

[oddlama]

also from tweakin, and apparently also from quark.

how it works: pick up a slime by right-clicking it with an empty bucket. You receive a slime in a bucket. If you are standing in a slime chunks the slime will cutely wobble up and down. I'd like to use the same animations as in quark, but we need to ask Vazkii for permission as it will be hard to properly attribute the texture in-game.

[oddlama]

Got permission from Vazkii a while ago, implementing this now :)