58 standardise parent class

[retinfai]

Standardise the parent class:
All environments (including CarGoal) extend the F1tenthEnvironment (prev CarGeneralEnvironment)
The responsibility of the F1tenthEnvironment is to handle all the subscriptions/publishers, which includes the publishing of the velocity commands as well as the fetching of the raw data.

From there, the child defines the environment specific information – eg. move OBSERVATION_SIZE to child class. In addition defines the get_observation, is_terminated.

Extracted functions that shouldn't be in a class into the util.py and termination.py.

Also, merged the CarTrack Environment classes :

Renamed the tracks:

• track_1.sdf
• track_2.sdf
• track_3.sdf

ClientSide:

• Pass the track name into as parameter CarTrackEnvironment(..., track='track_1')

ResetSide:

• Update the cartrack.launch.py to take the track name as launch argument passed when including it in the train.launch.py.
• Also added config support – can define the track inside the train.yaml file.

[Bac0nEater]

Thanks for cleaning my mess