NAME:
  hstinitstar
 PURPOSE:   (one line only)
  Initialize data and fitting parameters for a star fit to HST WFC3 data
 DESCRIPTION:
 CATEGORY:
  Astrometry
 CALLING SEQUENCE:
  hstinitstar,dblun,idx,hidx,error
 INPUTS:
  dblun - pre-opened LUN for a database connection, if provided, the LUN
            is left open..  If connection is not open, then it is opened
            at the start and closed at the end.
  idx   - index number of star to be fitted (stars table)
  hidx  - index number of image to be fitted (header table)
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
  error - Flag, set if an error occurred in setting things up
 KEYWORD OUTPUT PARAMETERS:
 CONFIGURATION: (optional, overrides xtrack.in)
   File: config.ini
   [global]
     subdir   - naem of sub-directory  added to base path to find data
     objectid - object code (see ephem.pro)
     boxmrad  - search half-width for peak of source, default=3
     hstpsf   - directory for psf cache
     satur    - Saturation signal level, default=80000L
     filetype - type of file to read ('flt' or 'flc'), default='flc'
   [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:
 PROCEDURE:
  This procedure sets up the common block for fitting
 MODIFICATION HISTORY:
  2020/06/23, Written by Marc W. Buie, Southwest Research Institute, cloned
                 from init_star.pro in the 15405 reduction directory.