Add Effect to change a biome

[reicheltp]

• Add celtic_rituals:change_biome effect

  Change Biome

  Changes the biome around the ritual center.

  param	value
  effect	celtic_rituals:change_biome
  biome	Name of the biome. E.g. minecraft:plains
  radius	(optional) size of the area around the center. Defaults to 5

Also required to add a custom network message as minecraft is not able to inform loaded chunks that a biome has changed. See: See: https://wiki.vg/Chunk_Format#Biomes

[reicheltp]

We still have a minor render issue when biome is changed through a ritual bag. See #55