Prevent subthreshold GRBs from overwriting GRBs
This partially addresses #393 (closed) for the case where subthreshold Fermi GRBs overwrite existing threshold GRBs, appending sky localizations and values that are often worse.
This partially addresses #393 (closed) for the case where subthreshold Fermi GRBs overwrite existing threshold GRBs, appending sky localizations and values that are often worse.