Issue 394 src rcv python

[lsawade]

Description

Pull request for sources and receivers defined through Python.

Issue Number

Closes #394

Checklist

Please make sure to check developer documentation on specfem docs.

• I ran the code through pre-commit to check style
• My code passes all the integration tests
• I have added sufficient unittests to test my changes
• I have added/updated documentation for the changes I am proposing
• I have updated CMakeLists to ensure my code builds
• My code builds across all platforms

[lsawade]

Both Sources and receivers can now be defined from python. see specfempp-py repo.

[Rohit-Kakodkar]

LGTM

[Rohit-Kakodkar]

Can you add @code and @Endcode doxygen directives here

[lsawade]

The recent updates change the source-file parameter to sources and it now can now be either a YAML node or a string pointing to a file.

[lsawade]

The updates also include zero-padded filenaming for the plotter output

[lsawade]

Finally I have updated the stations-file parameter to be named stations so that both receivers and stations follow the same pattern (almost)

receivers:
    stations: path/to/receiver_file || yaml node

sources:
    sources: path/to/source_file || yaml node

[lsawade]

there are a lot of files changed, but it's all specfem_config.yamls