Results 3 issues of Mihir Tripathi

This is the base code for implementing Bayesian Excess Variance (bexvar) in Stingray (#582). This project is part of Google Summer of Code 2022, a brief summary of the project...

Some functions in gti.py (e.g, `create_gti_mask()`, `create_gti_mask_complete()`) do not provide support for Lighturves created with Non uniform `dt`.