gym pytorch RL integration

[aredier]

the aim of this is to create a tutorial to show how to implement a RL pipeline with chariots using Gym environments and pytorch. The aim is also to implement all necessary changes in chariots to make this process streamlined

• Gym integration
• pytorch support
• control flow in chariots (abiltiy to create training loops and early stoping procedure will be central to implement RL environments)