NoTanks remix with mid-engine setup

This is a remix of Swepet's excellent NoTanks with the following modification:

* Slightly larger chamber
* Mid-Engine setup
* Printed pinion gear
* cover plates with cut out for modules
* FPV front cover module
* Exhaust fan rear cover module
* track links for 1mm paperclip hinge
* rubber-band track link insert
* outer side with holes
* gear wheel base with swappable gear ring

--- June 2019 update ---
Added a LED light, changed to use a different camera, and reduced the size of the front module. Please check the 3 stl files that begins with "notanks_remix_camera"

I also changed to metal pinion gear - the nylon ones still wear out after a while, especially when I have your tank stuck and still push on the motor. For the shim of the metal gear, I just cut strips of soda can and wrap it around the motor shaft.

The camera is this one:
https://www.ebay.com/itm/263827304354

LED light:
https://www.banggood.com/12V-Motorcycle-Handlebar-LED-Headlights-Running-Spotli