Merge multiscale and non-multiscale steps

docs/source/parset.rst

examples/rapthor.parset

rapthor/lib/parset.py

rapthor/lib/sector.py

rapthor/operations/calibrate.py

rapthor/operations/image.py

rapthor/operations/mosaic.py

rapthor/operations/predict.py

rapthor/pipeline/parsets/calibrate_pipeline.cwl

rapthor/pipeline/parsets/image_pipeline.cwl

rapthor/pipeline/parsets/image_sector_pipeline.cwl

rapthor/pipeline/parsets/predict_pipeline.cwl

rapthor/pipeline/steps/ddecal_solve_complexgain.cwl

rapthor/pipeline/steps/ddecal_solve_complexgain1.cwl

rapthor/pipeline/steps/ddecal_solve_complexgain2.cwl

rapthor/pipeline/steps/ddecal_solve_complexgain_debug.cwl

rapthor/pipeline/steps/ddecal_solve_scalarcomplexgain.cwl

rapthor/pipeline/steps/ddecal_solve_scalarphase.cwl

rapthor/pipeline/steps/predict_model_data.cwl

rapthor/pipeline/steps/predict_model_data_phase_only.cwl