Access Transformer Changes

AT changes and corresponding class changes.
Additions (all made public):
EntityLiving.targetTasks
PotionHelper.potionRequirements
PotionHelper.potionAmplifiers
PotionEffect.duration
Potion.setIconIndex
Item.setPotionEffect
Block.blockHardness
Block.blockResistance
Enderman Teleport Event

New event when an enderman teleports that allows the teleport location
to either be modified or completely cancelled.