GoPro Session Superview Case for Modular Multicopter Mounts

I remixed [mr2fpvninjas](http://www.thingiverse.com/mr2fpvninjas/about)'s fantastic [THE Gopro Session Superview cover for FPV quadcopters etc](http://www.thingiverse.com/thing:1791443) with the following changes:

- Added tabs for a 20mm battery strap for use on modular mounts
- Tabs include hard coded printing support since I couldn't get Cura to cooperate
- Made the hole in the back bigger and added a cutout so the Session's back button is accessible

I use it on my [x210 V+ GoPro S