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* Added ``recursive`` and ``n_proc`` keywords to ``mp_batch``, and changed return type to ``None``.
* Changed source tree structure for better clarity.
* Renamed ``run_batch`` to ``run_batch_lst``.
* More internal improvements.
* Z-axis bins range is equal, i.e. each bin spans the same axial distance in microns.
* Travis CI is back on.
* Added option to run PySight with a predetermined config file: ``main.run(cfg_file='/path/to/file.json')``.
* New integration tests.