No information anywhere about which arc is being used during a GMOS LS reduction

[KathleenLabrie]

An arc is required for QECorrect and distortionCorrect. Both call getProcessedArc. Nowhere in logs, in the headers, or in the provenance table is there a record of which processed arc was used.

getProcessedArc: The getProcessedBias and getProcessedFlat both list which calibration is being picked up for each input frames. This does not seem to happen for getProcessedArc and it needs to be fixed.

PROVENANCE table: The bias and the flat being used are recorded. But the arc is not. It really should.

Headers: While I personally would really like to see the name of the arc used in a header keyword, looking at the headers, I see that this is not done for the other calibrations. Yes, the info is (should be) in the provenance table. The list of inputs in a stack is in the headers though.

Executive summary: The name of the arc used must be recorded somewhere.