NAME:
  qhygpsavg
 PURPOSE:   (one line only)
  Average one or more files of GPS log data from a QHY174GPS camera
 DESCRIPTION:
 CATEGORY:
  Miscellaneous
 CALLING SEQUENCE:
  qhygpsavg,date
 INPUTS:
  date - string with a date to process (YYYY-MM-DD)
             ignored if FILE keyword is provided
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
  DIR  - Directory to scan for data (default is current)
  FILE - Specific list of files to process (overrides date input variable)
 OUTPUTS:
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  2018/11/25, Written by Marc W. Buie, Southwest Research Institute