96 Fix RailEnvPersister incomplete.

[chenkins]

Changes

• Add hashable state implementation to support == which is also human-inspectable (RailEnv.__getstate__) dictionaries.
• Extended RailEnvPersister for missing items.
• Persistence benchmarks
• TODO lru cache problem
• TODO regression tests.
• TODO documentation comparison (feature completeness and performance).

Related issues

Fixes #96.

Checklist

• Tests are included for relevant behavior changes.
• Documentation is added in the docs folder for relevant behavior changes. If you made important user-facing
  changes, describe them under the [Unreleased] tag in CHANGELOG.md.
• New package dependencies are declared in the pyproject.toml file.
  Requirement files have been updated by running tox -e requirements.
• Code works with all supported Python versions (3.10, 3.11 and 3.12). Checks run with all three version and are
  required to run successfully.
• Code is formatted according to PEP 8 (an IDE like PyCharm can do this for you).
• Technical guidelines listed in CONTRIBUTING.md are followed.

[SergeCroise]

see a few lines above:
def close(self):
"""
This method closes any renderer window.
The same in :
def render(self, ...

[chenkins]

Provisional results bench_persistence.py for 200 x 200 grid with 100 agents:

## Matrix                                real    [01]    [02]    [03]    [04]    [05]
[01] RailEnvPersister                  0.1689   100.0   119.9   378.4   916.5  1437.2
[02] SerializationDeserializion        0.2024    83.4   100.0   315.7   764.7  1199.1
[03] get_state+msgpack                 0.6389    26.4    31.7   100.0   242.2   379.8
[04] get_state+pickle                  1.5475    10.9    13.1    41.3   100.0   156.8
[05] get_state+json                    2.4267     7.0     8.3    26.3    63.8   100.0

=========================================
{'RailEnvPersister': '122.175MB', 'get_state+pickle': '163.011MB', 'get_state+msgpack': '163.124MB', 'get_state+json': '163.127MB', 'SerializationDeserializion': '122.415MB'}

[chenkins]

Results same setup bench_persistence.py for 200 x 200 grid with 100 agents.
after profiling -> fc48262

## Matrix                                real    [01]    [02]    [03]    [04]    [05]
[01] get_state+msgpack                 0.0944   100.0   176.7   182.6   254.7   404.2
[02] RailEnvPersister                  0.1668    56.6   100.0   103.3   144.1   228.7
[03] SerializationDeserializion        0.1724    54.8    96.8   100.0   139.5   221.4
[04] get_state+pickle                  0.2405    39.3    69.4    71.7   100.0   158.7
[05] get_state+json                    0.3816    24.7    43.7    45.2    63.0   100.0

=========================================
{'RailEnvPersister': '122.175MB', 'get_state+pickle': '40.941MB', 'get_state+msgpack': '41.054MB', 'get_state+json': '41.057MB', 'SerializationDeserializion': '122.404MB'}

[chenkins]

Results same setup bench_persistence.py for 200 x 200 grid with 100 agents.
after adding dev_obs_dict 0527f69

## Matrix                                real    [01]    [02]    [03]    [04]
[01] SerializationDeserializion        0.1199   100.0   108.0   134.5   187.5
[02] RailEnvPersister                  0.1294    92.6   100.0   124.5   173.7
[03] get_state+msgpack                 0.1612    74.4    80.3   100.0   139.5
[04] get_state+pickle                  0.2248    53.3    57.6    71.7   100.0

=========================================
{'RailEnvPersister': '122.424MB', 'get_state+pickle': '41.190MB', 'get_state+msgpack': '42.059MB', 'SerializationDeserializion': '122.400MB'}