Godot-rl

Fixes issue where linux builds were including in the environment.yml file.

Merges PR 13

Implemented a number of features, bug fixes and improvements to the documentation.

- Including an updated sensor suite.
- New checkpoints for the updated sensors.
- The conda environment should now work out of the box and support GPUs. 8 9
- Fixed a bug with the reward function in the BallChase env 11
- Improved documentation 7

Includes 4 example games and wrappers for Ray RLlib and StableBaselines3