Diffractio

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Alpha state

* Improvement to documentation (readthedocs)

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Alpha state

* convert_mask -> extrude_mask
* Improved documentation
* Implemented PWD
* Reduced size of html

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Alpha state

* Finished first version of examples and tutorial.

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Alpha state

* Included vector (fields, sources, masks) modules, tests, and tutorial.

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Alpha state

* copyreg removed (previous not worked)
* change fft to scipy: "from scipy.fftpack import fft, ifft, fftshift"


First release on PyPI in pre-alpha state.

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Pre-alpha state.

* Modules are passed to python3.