Change payload of MOVE packets

Need the ability to provide several positions.
WIP: Client implementation
Draw snake shape based on new move payload structure
Merge pull request #5 from avaly/payload-shape

Draw snake shape based on new move payload structure
WIP: move payloads to worm
Merge branch 'master' into payload
Create attachable

Create an interface to be able to attach several things together.
Use this to attach a tail to the worm.
Create embedded struct Block

Move attaching, positioning etc to separate struct
Enable tail of worm

A tail with default length of 10 blocks.

TODO:
	Collition detection