Carrier support for Wanhao Duplicator I3 Plus - fits original

Wanhao Duplicator I3 **_Plus_** is different from the standard one. There is a PCB behind the X carrier, in a metallic box - this design is a replacement of this box.

The original design is available on Tinkercad:
- https://tinkercad.com/things/ixOQnsZ7ymE

Variant for the CiiCooler (http://www.thingiverse.com/thing:2004629):
- http://www.thingiverse.com/thing:2050157