NAME:
   objast
 PURPOSE:   (one line only)
   Generate astrometry from Looker (obj) files
 DESCRIPTION:
 CATEGORY:
   Astrometry
 CALLING SEQUENCE:
  objast,objlist
 INPUTS:
  objlist - String (scalar or vector) of name of obj file to process.
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
  DDIR    - Directory where image data reside (default = current directory)
  GAIN    - Gain of CCD (defalt = 1.0)
  OBJRAD  - Object aperture radius (default=10)
  KEYLIST - header correspondence file
 OUTPUTS:
  Generates a .ast file for every 'y' object in each obj file.  Also, any
    objects marked with 's' are saved to the 'psf' sub-directory
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  Written by Marc W. Buie, Lowell Observatory, 2002/04/07
  2002/09/10, MWB, fixed bug for non-Mosaic data
  2003/10/01, MWB, converted my Delfile call to system file_delete routine
  2004/07/20, MWB, added support for implanted fake objects in obj files.