Zombie Pigmen behavior

At the moment, pigmen are absolutely no challenge and are totally being ignored by normal players.

Adult zombie pigmen could have their "sleeping" status removed if a player jumps, runs or digs blocks around them in a 5 blocks radius. 10 blocks radius for the baby pigmen, for they are more "aware" than their "sleepy" adult forms. This would force players to be much mure careful around pigmen, and sneak when within their awareness range. Only the respective pigman would wake up and charge at the player, though. The other pigmen still would only become active if the player hurts that pigman. This would force the player to disable that pigman without (actively) hurting it, for example by imprisoning it in blocks. If woken up that way, there could be a check done every 10 seconds whether the player is still within a 20 blocks radius. If not, the pigman would fall back to sleep.

This would spice up the standard nether mob fights again, which presently are not present, except for ocasionally spawning ghasts. The nether fortresses are spicy enough at the moment.