A-Max Anura Antenna mounts + cam mount

I ended up not using this frame, but I did create some parts for it. They're mostly untested, but were checked for fit. Print in TPU.

- The cam mount is set at 30° if using a camera with 3 mounting holes, and allows the camera to be mounted further forward, since with the original mounting, an angle of more than 20° is not possible. If using just the center hole, you can freely rotate the camera at the angle you want.
- The XT30 and RC antenna mount requires a drop of superglue to keep the X