NAME:
  getlclmid
 PURPOSE:   (one line only)
  Compute the time of the next local midnight
 DESCRIPTION:
 CATEGORY:
  Astronomy
 CALLING SEQUENCE:
  jdlclmid = getlclmid(jd,lat,lon)
 INPUTS:
  jd - Julian date or calendar date-time string (see jdparse.pro)
        If the string is empty or the date is negative, then the system
          clock is used to set the time.
  lat - Latitude of observatory (radians or sexegesimal string)
  lon - West longitude of observatory (radians or sexegesimal string)
 OPTIONAL INPUT PARAMETERS:
 KEYWORD INPUT PARAMETERS:
 OUTPUTS:
  Return value is the JD (UTC) of the nearest local midnight.  This may be in
   the past.
 KEYWORD OUTPUT PARAMETERS:
 COMMON BLOCKS:
 SIDE EFFECTS:
 RESTRICTIONS:
 PROCEDURE:
 MODIFICATION HISTORY:
  2018/05/22, Written by Marc W. Buie, Southwest Research Institute