Whitelist for electrifying other sheep

[tali713]

Not sure if this a bug or a feature request but...

Currently because of the way it is tested The only sheep which may be energized by lightning are vanilla sheep. This is unfortunate, why can't the twilight forests sheep be transformed into a source of energy, and then there is of course Animania, which by default replaces sheep with their own sheep and goat variants.

Of course, this is simply solved by using instanceof, with one or two minor draw backs When struck by lightning Energetic Sheep will now have their wool restored rather than catch on fire. I have mixed feelings about this. Energetic Sheep from Animania will always have white wool and should goats really count?

[rubensworks]

A better way to handle this, might be to work with an entity class whitelist. Twilight forest and animania animals could then be added to this list.