CAL_LAC: CAL Zero-Suppression register settings

The CAL_LAC precinct controls zero suppression (log accept) thresholds for reading out CAL data.

• Registers:
  

  Group	Register Name	Instances	Multiplicity	Subsections	Type	Width (bits)
  CFE	log_acpt	16 x 4 x 4 x 12	1	1	mask	16

• Methods: BCAST | CALIB | SETTINGS
  SETTINGS uses an ancillary file to set all the registers.
  CALIB uses an ancillary calibrations file and constants to set all the registers.
• Ancillary files:
  CAL_LACSettings.
• Constants:
  LAC_MeV: log accept threshold energy in MeV.