NAME:
  rdplast
 PURPOSE:   (one line only)
  Read ``plast'' output files (object lists for astrometry)
 DESCRIPTION:
 CATEGORY:
  File I/O
 CALLING SEQUENCE:
  rdplast,plastfile,name,mag,num
 INPUTS:
  plastfile - Name of file to read
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
  name   - String array of names of objects
  code   - String array of object codes (with c and e prefix)
  mag    - Array of magnitudes for objects
  num    - Number of objects read from file, if this is 0 then name and mag
              will may be undefined.
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  Written by Marc W. Buie, Lowell Observatory, 2002/08/16
  2002/10/23, MWB, fixed a LUN leak for empty plast file reading.
  2005/03/11, MWB, fixed a problem with comet names in a pla file.
  2007/06/19, MWB, added special case for P objects (must be in file with
                    lower case p).  This triggers JPL ephemeris object.