NAME:
  astprmt
 PURPOSE:
  Promote version of an astrometry fit coefficient file to highest version.
 DESCRIPTION:

 CATEGORY:
  Astrometry
 CALLING SEQUENCE:
  astprmt,fitfile,centers
 INPUTS:

  fitfile - File with astrometry fit coefficients (Default=fitcoeff.dat)

  centers - File with image centers.  (Default=centers.dat)

 OPTIONAL INPUT PARAMETERS:

 KEYWORD INPUT PARAMETERS:
  RENORMFAC - This input is needed when promoting across the v1.1 and v1.2
                 version boundary.

 OUTPUTS:

  The fitfile is updated to the most recent version.  Not changed if already
    current or if there is an error reading the file.

 KEYWORD OUTPUT PARAMETERS:

 COMMON BLOCKS:

 SIDE EFFECTS:

 RESTRICTIONS:

  Normally, this routine will always promote file that is not at the latest
    version level.  However, if the version is v1.1 and RENORMFAC is not
    provided, the file will not get promoted.  If you can provide RENORMFAC
    then the file will always get promoted if needed.

 PROCEDURE:

 MODifICATION HISTORY:
  1997/10/09, Written by Marc W. Buie, Lowell Observatory
  2000/01/19, MWB, added version 1.1 support
  2009/08/05, MWB, added version 1.2 support, total rewrite to eliminate
                 duplicated code between here and RDASTFC.PRO
  2009/12/01, MWB, upgraded to version 1.3 support