NAME:
  logusage
 PURPOSE:   (one line only)
  Record a usage line to a log file
 DESCRIPTION:
 CATEGORY:
  File I/O
 CALLING SEQUENCE:
  logusage,name
 INPUTS:
  name - this is the name of the calling program.  Designed to use the
           self variable commonly used with badpar calls.   Looks like
           'name: '.  This rountine will using non-blanks characters
           up to but not including the colon when printing to the log file.
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
  LOGFILE - name of the log file to append to.  Default is 'usage.log'
 OUTPUTS:
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
  Each time this routine is called, a line is written to the log file.
     hostname   name   Time (UT) of call
  The host name is the simple (non-qualified) name of the host.
  name is the input variable
  The time is YYYY-MM-DDThh:mm:ss.  This can be parsed back to JD with jdparse
 MODIFICATION HISTORY:
  Written by Marc W. Buie, Southwest Research Institute, 2018/10/13