Part 1 partial fix for #2192 complex numbers

[willend]

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Please describe what your PR is adding in terms of features or bugfixes:

Draft implementation with wrapper functions for complex arithmetics.
(Should work also with MSVC that does not implement the standard operators...)
Partial fix for #2192, issue will be updated with remaining work.

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Development OS / boundary conditions

Please describe what OS you developed and tested your additions on, and if any special dependencies are required:

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