NAME:
  hstmeasure
 PURPOSE:   (one line only)
  Measure a science target position in an HST WFC3 image
 DESCRIPTION:
  This tool uses extracted sub-arrays to permit measuring a source
    location.  It is designed for moving targets and the position is
    saved for later use either as is, or, as a starting location for
    some other fitting program.
 CATEGORY:
  Astrometry
 CALLING SEQUENCE:
  hstmeasure,fn
 INPUTS:
  fn - file name for the extracted sub-array to be measured
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
 KEYWORD OUTPUT PARAMETERS:
 CONFIGURATION: (optional, overrides xtrack.in)
   File: config.ini
   [global]
     subdir   - name of sub-directory  added to base path to find data
     tdw      - Fitting region half-width for stars, default=15
   [ddir]   - section to list potential root directories to find data
     XXX - 
       XXX is a unique string (eg., D01)
        is a directory path
       for additional details see getddir.pro
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
   Uses the hstast mysql/mariadb database table
 PROCEDURE:
 MODIFICATION HISTORY:
  Written by Marc W. Buie, Southwest Research Institute, 2020/10/05