Description

   The Compare Interval Time routine compares two binary timestamps
   and returns a flag indicating that the first time is greater
   than, less than, equal to, or overlapping with the second time.
   Two times overlap if the intervals (time - inaccuracy, time +
   inaccuracy) of the two times intersect.

   The input binary timestamps express two absolute or two relative
   times. Do not compare relative binary timestamps and binary
   timestamps. If you do, no meaningful results and no errors are
   returned.

   This routine does a temporal ordering of the time intervals.

   utc1 is utc_lessThan utc2 iff
           utc1.time + utc1.inacc < utc2.time - utc2.inacc

   utc1 is utc_greaterThan utc2 iff
           utc1.time - utc1.inacc > utc2.time + utc2.inacc

   utc1 utc_equalTo utc2 iff
           utc1.time == utc2.time and
           utc1.inacc == 0 and
           utc2.inacc == 0

   utc1 is utc_indeterminate with respect to utc2 if the intervals
   overlap.