Select monster types have issues with Entry/Electric flags

[skore87]

Only two entities that aren't working as expected with the addition of custom entities and events to catch movement.

MagmaCube - Doesn't seem to trigger BPEntityMoveEvent
Slime - Infinitely splits against the ELECTRIC flag with the current event hook setup. Could be used to make an exploit farm for slime balls.

[skore87]

Stopped infinite split issue by not damaging the slime.

[skore87]

Slime issue should be completely fixed now. New custom entity is given the original's size. Will close when tested. Still need to retest the magma cubes again though.