update fep1_mong_check for acis_thermal_check 3.0

[jzuhone]

Description

This PR implements an update to achieve compatibility with acis_thermal_check version 3.0 (PR acisops/acis_thermal_check#25). In essence, it does the following:

1. Subclasses ACISThermalCheck to FEP1MongCheck` and stores all of the information specific to the FEP1 Mongoose model inside this class, such as validation limits, histogram limits, etc.
2. calc_model becomes the _calc_model_supp method which overrides a stub in the ACISThermalCheck class. This is designed to put the common model functionality in the super class and allow for model-specific customizations to be carried out in this method.
3. Command-line arguments are now passed to the run method instead of the class __init__.
4. Incorporates the new acis_thermal_check testing machinery and stores answers inside the package

Testing

• Passes unit tests on MacOS, linux, Windows (at least one required)
• Functional testing