Area Gauss/Drude

[Dhruvil2911]

In this PR, I've used area (power) as the parameter instead of the amplitude to fit Gaussian and Drude profiles. I've made 2 classes AreaGaussian and AreaDrude in the component_models file corresponding to each profile. There are corresponding changes in the helpers, base, and feature_strength files. I have also created an ipac file with the area columns (scipack_ExGal_area_1.ipac). The command > run_pahfit M101_Nucleus_irs.ipac scipack_ExGal_area_1.ipac will demonstrate the changes.

For feature_strengths of Gaussian/Drude, I have simply equated it to the area (power).