psl examples

[drgona]

@aarontuor @aaron-tuor @madelynshapiro

The current toml file does not include all the dependencies necessary to run psl examples in:
https://github.com/pnnl/neuromancer/tree/master/examples/psl

there are broken notebook examples:

• https://github.com/pnnl/neuromancer/blob/master/examples/psl/signals.ipynb
• https://github.com/pnnl/neuromancer/blob/master/examples/psl/systems.ipynb

all psl examples lack proper documentation to guide the user through the functionality of the library

There are also broken psl examples in the test folder:
https://github.com/pnnl/neuromancer/blob/master/tests/psl/coupled_sys_test.ipynb

Missing dependencies:

• pygame-menu
• stable_baselines3

Failing tests in: psl\test_directory.py
assert os.path.normcase(nm_path1)==os.path.normcase(nm_path2), 'installed neuromancer root directory not the same as test root directory' AssertionError: installed neuromancer root directory not the same as test root directory

I am of strong opinion not to include all these psl_gym dependencies in our base environment.
the pygame visualisation should be a separate project independent of Neuromancer for now

[madelynshapiro]

All pslgym code has been removed by #69 . Broken notebook examples are still TODO:

• /examples/psl/signals.ipynb
• /examples/psl/systems.ipynb