Changed
=======
Speed up lookups in IntervalDict for non-interval keys.
Speed up iterate by no longer creating singleton instances under the hood.
Drop official support for Python 3.6.
Fixed
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Infinite recursion when a subclass of an Interval is compared using > with an Interval instance (see #75).
Signed-off-by: Wang Mingyu <wangmy@fujitsu.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>
