[FEATURE] Improve rtd documentation

[birgits]

The readthedocs documentation needs some improvements and additions:

• It should be automatically checked if links work correctly (compare Add github action to check links #201)
• Examples in the documentation should be automatically checked (could e.g. be converted to notebook that is integrated into documentation and tests)
  • Minimum working examples
  • Usage details
• New plotly plot options should be added here
• Add electromobility to usage details and features in detail
  • Add information on how to retrieve SimBEV and TracBEV data
  • Add information on electromobility class
  • Add information on how charging processes are allocated to charging stations (could also be further explained in docstring of distribute_charging_demand function)
• Add jupyter notebook examples
  • Basic example
  • Plotting example
  • EV example

[mltja]

Maybe the examples of the documentation can be checked with doctest?

Using ding0_test_network_2 for the examples in Getting Started.

[birgits]

@maike93he where did you implement checking the links and examples in the documentation? I would like to have a look at it.

[maike93he]

Added you @birgits as a reviewer for the two pull requests regarding links and examples check in doc.

[birgits]

Parts of this are implemented in PR #292. The PR, however, needs to be cleaned up and current dev merged.