ENH: Prefilter hooks for pipeline #218
Description
Some users may find it useful to use a "prefilter" for PV system operational issues, like from an existing QA pipeline. Currently there is no easy way to include this information in the pipeline and loss analysis routines.
I propose adding an optional kwarg to the run_pipeline method for a Boolean array with a length equal to the number of days. A "True" value means that day of data should be included in the pipeline, and a "False" value means the data should not be included. This array would be combined with the pipeline's estimate of days with operational issues, and the "bad" data flag would be updated to remove days that don't pass the pre-filter. This ensures that all downstream subroutines exclude the data from the pre-filter, including clear/cloudy day labeling, clear sky estimation, and loss factor estimation.