Add option to fit only groups X-Y to ramp fitting

[stscijgbot-jp]

Issue JP-3777 was created on JIRA by David Law:

One request that has come up fairly often in discussion with both instrument teams and more advanced science groups is option to provide ramp fitting with a start and end group to fit ramps between.  For MIRI in particular, this is quite useful for studying detector artifacts, nonlinearity, and etc.

Presumably the simplest way would be to allow input of a groupmin/groupmax parameter, and set DQ to DO_NOT_USE outside of these bounds.

Low priority as workarounds exist, although tedious (easiest way I've found is to hack the SATURATION step).  Likewise, this is a change more focused on instrument teams and advanced users rather than something that directly improves data products or the pipeline for typical users.

[stscijgbot-jp]

Comment by Jane Morrison on JIRA:

The ground testing MIRI DHAS software had options of selecting the starting group and ending group for the fit. We found that very helpful to study detector effects better and to avoid regions of the ramp we did not have a decent correct (start of the ramp because of RSCD for example).