Kodo

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* Minor: Added ``symbols`` and ``symbol_size`` methods to factory.
* Minor: Added graphical Lena example.
* Major: Update kodo to version 20.
* Major: Update sak to version 13.
* Major: Update fifi to version 15.
* Major: Added recycle as a dependency.
* Major: Rename classes to follow the new naming scheme of kodo.
* Major: Use proper python naming style for classes. E.g., the
``full_vector_encoder_binary``is now called ``FullVectorEncoderBinary``.
* Minor: Added graphical print_coefficients example.
* Minor: Added a more simple kodo python API, ``pykodo``.
* Minor: Collected example helper logic for graphical exemplification and put
it in ``kodo_helper`` module.

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* Major: Upgrade to Fifi 14.
* Major: Upgrade to Kodo 19.
* Minor: Added ``sparse_full_rlnc_encoder``.
* Minor: Added guide on how to extend the bindings.
* Patch: Fix the docstrings to follow the pep257 style guide.
* Patch: Added keyword argument for the ``is_symbol_pivot`` method.
* Minor: Added UDP unicast example.

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* Minor: Added multicast examples.
* Major: Python objects now only provide the functions they support. E.g., a
non-trace encoder no longer has the trace function. Also the ``has_``
functions were removed. This includes: ``has_partial_decoding_tracker``,
``has_systematic_encoder``, and ``has_trace``.
* Patch: Simplified examples.
* Major: Updated Kodo 18.
* Major: Updated Fifi 13.
* Major: Updated Sak 12.

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* Minor: Added documentation for the python functions.
* Minor: Added keyword arguments for the python functions.
* Patch: Removed unused dependencies guage and tables.

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* Minor: Set ``kodo-python`` as the name for wscript target, so that it doesn't
clash with the kodo dependency when both are used as dependencies.

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* Major: Updated to Kodo 17.
* Minor: Extended API.
* Minor: Added additional examples.