Simplify dependencies

[kadykov]

Since the tmm-fast is published on pipy.org I think it is better to keep dependencies as minimal as possible.

For instance, it would be better to remove dask from dependencies, as it is not directly used anywhere in the project.

The main functionality in vectorized_tmm_dispersive_multistack.py and tmm_fast_torch.py does not require gymnasium, matplotlib and seaborn, therefore we can declare them as optional ones.

Probably, it could be even better to split the TMM and AI functionality into two separate projects...

[Nerrror]

You're right, it might be a good idea to split the TMM and AI functionality and add a second project which then builds on TMM for the RL environment.
This could be implemented in the next main version or so. I'm working on an extension for incoherent layers right now so this issue might take a while to implement