#23 Let players put nets into spawners

Add the ability to change spawner types by right-clicking them with a safarinet. This should be permission-based per mob, and by primitive mobs. Primitive Mobs are mobs without any equipment, effects, attributes etc. Examples: `safarinet.changespawnertype.primitiv.zombie` would allow you to change a spawner type to a primitive spawn type. Putting in a non-primitive net would convert the mob to a primitive type. `safarinet.changespawnertype.nonprimitive.zombie` would allow you to put any zombie type in it.