NAME:
  uniqueid
 PURPOSE:   (one line only)
  Create a unique identifying string
 DESCRIPTION:
  This routine will construct a 6-character string (base 32 number)
    that is close to being a unique string.  The odds getting an identical
    string in close temporal proximity is low but not zero.  You need to
    take extra steps to make sure it is unique before counting on that
    property.  This tool is mostly designed to help support parallel
    processing.
 CATEGORY:
  Utility
 CALLING SEQUENCE:
  id=uniqueid()
 INPUTS:
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
   mwb_uniqueid_com - used to hold a persistent random number seed for
     successive calls.  This is not designed to be used by any other
     program.
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  Written by Marc W. Buie, Southwest Research Institute, 2011/07/19