Handle Mana Bursts

[Eufranio]

There is no official way to handle the Mana Burst entity. My opnion is that MyTown handle it like a player, because when using a Mana Blaster, the UUID of the shooter is stored in the burst (then we can check if the owner has permission), and if the shooter is null, handle it as a fake player or similar (because the burst was emitted by a Mana Spreader, not a player).

We can block the Mana Blaster right click actually, but can't block players putting lenses in mana spreaders and destroying nearby towns with the mana bursts, neither we can block placing mana spreaders near towns, because the problem of cities.