In the time honoured tradition of trying to fix vanilla, we today attempt to patch the pathfinding AI so that it doesn't lag when
there's a lot of entities. Basically, if the zombie can't reach the villager, backoff subsequent pathfinding attempts. Hopefully
should really help with lag caused by zombie swarms.
Updated FML:
MinecraftForge/FML@b993cf4a9825865b3a8a0c7b083c23d56dbd1d6f More exception handling for less derpiness.