Ars magica coremod removal changes

-Added Entity extended properties, along with register and get functions

-Added IExtendedEntityProperties interface, which is required to register with extended properties

-Added EntityConstructing event, which is required in order to have extended properties registered before the NBT read happens.

-Added PotionBrewed event handler

-Brewing stand & slots changed to look for instanceof ItemPotion rather than Item.potion.itemID for valid brewing items

-Added event for when a player falls but has the ability to fly (the normal fall event does not proc in this case)

-Added EnderTeleportingEvent which occurs when an enderman is about to teleport or when an ender pearl is used.  The resulting coordinates can be manipulated or the event can be canceled, which will cancel the teleport.

-Added some access transformer changes