a time range ?tr1 and a time range ?tr2 overlaps.
(<=> (Overlaps ?Tr1 ?Tr2)
(And (Tp< (Time-Range.Start-Time ?Tr1)
(Time-Range.Start-Time ?Tr2))
(Tp< (Time-Range.Start-Time ?Tr2)
(Time-Range.End-Time ?Tr1))
(Tp< (Time-Range.End-Time ?Tr1) (Time-Range.End-Time ?Tr2))))