Revised implementation of SICOR. Added sicor to package dependencies. Updated CI docker image recipe.

Added io.reader.Solar_Irradiance_reader().
Added model.srf.py for handling spectral response functions + test_srf.py.
Extended metadata reader with srf and solar_irrad attributes.
Refactored TOARad2TOARef_Transformer to Radiometric_Transformer.
Removed deprecated dummy TOARef transformer.

Added test_config.py.
Fixed linting issue.

Updated docker container builder. Updated test_enpt_install CI job. Updated project dependencies. Updated version info.