-------------------
- Coordinate frames now have a "native" order and then are sorted based on ``axes_order``. [457]
- ``WCS.numerical_inverse`` no longer accepts high level objects (``with_units=`` is not supported) use ``WCS.inverse``. [457]
- ``CoordinateFrame.coordinates`` has been replaced by ``CoordinateFrame.to_high_level_coordinates`` [457]
- ``CoordinateFrame.to_quantity`` has been replaced by ``CoordinateFrame.from_high_level_coordinates``. [457]
- Inputs to ``CelestialFrame``, such as ``axes_names`` are now explicitly in lon, lat order and will re sorted based on ``axes_order=``. [457]
- Implement code linting and automatic formatting. [544]
- Refactor ``WCS`` to use a ``Pipeline`` base class which adds basic checks to ensure that the pipeline is valid. These
include checking for duplicate frame names and that the last transform is ``None``. [545]
- Bugfix for ``WCS.invert`` and ``WCS.to_fits`` that prevented evaluation when the attached bounding box happened to have
units on its values. [554]