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# Conflicts:
#   nifty5/operators/energy_operators.py

improve docstring

See merge request ift/nifty-dev!168

Mr docs

See merge request ift/nifty-dev!166

Docs pa

See merge request ift/nifty-dev!164

Furthermore, the zero_mode keyword is gone for AmplitudeOperator. It is not used
in the demos and is not really appropriate from a theoretical point of view
anyways. We will add in a better option later.

People who would like to check in pngs can still do it with the help of a
force-stage. Since we do not want to have pngs in the repository generally it is
sensible to have it in the gitignore file.

Multiplication of operators had worked before. Only multiplication with scalars
was not possible.