Accept partially calibrated inputs in calib_prep.py

[bhilbert4]

If the user supplies partially calibrated files as inputs, make sure that calib_prep.py can handle that and still produces the correct strun command to finish processing. Make sure it can still select the appropriate file version if any others or no others are found.

Make sure calib_prep.py examines the current calibration state of the input file even if other versions are found elsewhere. It may still be that the input file is the version that is needed. This is especially true if the user requests an uncal file.