Haenau - Update

A few minor changes, to the front motor mounts.
and a re-design for the back mounts.

Also a NEW E3D - easy swap print head dolly,
and an untested 'DIAMOND HEAD' mount,
> still waiting for MK8 extruders from china, so cannot test it :(

Videos:
First print, Marvin - https://youtu.be/JAmZMetpKMQ
Some SERIOUS Z-Wobble: https://youtu.be/t6d9e5BzREk

Note: Z Wobble was because the threaded rod was not correctly fitted in the coupling !

Myself and my 10 year old daughter built this pr