Fractalshades

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- Added Perpendicular Burning Ship in arbitrary precision
Rev 0.5.1
- Added unskew option in interactive mode
- Added Tetration (power tower) fractal

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- Added Burning ship deep explorer
- Added unskew option in batch mode
- Chained Bilinear interpolations for arbitrary precision zooms
- Glitch correction after Zhuoran
(https://fractalforums.org/fractal-mathematics-and-new-theories/28/another-solution-to-perturbation-glitches/4360)
- Documentation: GUI now runs & output figures from Github headless runner
for interactive script examples

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- fixed typo in run_interactive.py

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- fixed concurrent.futures import

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- Improved Fieldlines default postproc when using mirrored cmap
- Typo name Disp_Layer -> Disp_layer
- added Collaz fractal
- use gmpy2 bindings through Cython C-extension for faster full-precision
calculations
- improved glitch correction : use single-reference based method
- use multi-threading + NOGIL compilation to improve portability under Windows
- build under windows
- added progress status bar
- cleaner separation of parameters by themes in GUI
- rotation in GUI
- Newton search in GUI
- When one quit and relaunch the GUI, all previous parameters are reloaded