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* ``_foundation`` has been renamed to ``_util``, and a lot of functions which were not being
used anymore have been removed.
* Add new unit category mass temperature per mol (``kg.K/mol``).
* Some units have been renamed as they were deemed out-of-place in the oil industry to something more usual (for example, ``1000ft3/d`` became ``Mcf/d``).
The old representation of those units is still supported, but they will be automatically translated during ``Quantity`` creation, so this change should not affect users much.
* Fix division ``1.0 / a`` where ``a`` is a ``Scalar`` or ``Array`` and also add support for floor
division, i.e., operations like ``a // b`` where ``a`` and ``b`` are ``Scalar`` or ``Array``
(and combinations with ``float`` or ``int``).
* Add new unit category for Joule-Thomson coefficient (``K/Pa``).
* Add new temperature unit for density derivative in respect to temperature (``kg/m3.K``).