--------------------------
* Added: support for
``None``,
``''``,
``'None'``,
``'NaN'``,
``'NaT'``,
``np.NaN``,
``pd.NA``,
``pd.NaT``
to represent ``NaN``
in ``audmath.duration_in_seconds()``
* Added: support for ``'Inf'``, ``'-Inf'``, ``np.inf``, ``-np.inf``
to represent ``Inf``, ``-Inf``
in ``audmath.duration_in_seconds()``
* Fixed: sign support in string values
(``'-1 ms'``, ``'+s'``)
in ``audmath.duration_in_seconds()``