Improve reference date option to avoid snow

[falkamelung]

How can we make sure that a summer scene is selected as the reference? I see two options:

minopy.interferograms.referenceDateMonth=September
minopy.interferograms.referenceDateSeason=Summer 

In the first case it could select the closest September scene from the middle of the stack

[mirzaees]

It is already implemented in miaplpy:

https://github.com/insarlab/MiaplPy/blob/e9a12d2fa25640b6cb043875a0a8a300ae111f85/miaplpy/defaults/miaplpyApp.cfg#L74