Rename member variables to follow convention of m_ prefix
Summary:
Rename member variables to follow convention of m_ prefix
In addition:
- Introduce pre-build check in the CI that the member variable naming convention is being followed in all classes
- Fix some shadowing of variables
- Fixes to Doxygen configuration
- Enable shadowing and overloaded-virtual compiler warnings
Test Plan: Run tests for all models using the results of the same tests on master as reference
Reviewers: jback, averbyts, kreps, abudinen
Reviewed By: jback, abudinen
Subscribers: #evtgen_admins
Tags: #evtgen
Differential Revision: https://phab.hepforge.org/D58