Minigrid Environment Testing

[juliusfrost]

I did the bare minimum to make minigrid work with our current code but there's a lot left to do to completely integrate it

• [x] Create custom model for minigrid agent
• [x] Create example configs for minigrid agent
• [x] Make video text scalable to video dimensions
• [x] Make user study text adaptable to different environments
• [x] Make exploration policies use trained policies to demonstrate more effective counterfactual states