Various minor header changes were made to improve clarity.
       Added mention that 'lt' returns a value in seconds.
 
   -CSPICE Version 2.0.1, 27-JUL-2003 (NJB) (CHA)

       Various header corrections were made.

   -CSPICE Version 2.0.0, 31-DEC-2001 (NJB)

       Updated to handle aberration corrections for transmission
       of radiation.  Formerly, only the reception case was
       supported.  The header was revised and expanded to explain
       the functionality of this routine in more detail.

 