Implementation of colormap "Turbo" (#15388)

* implemented turbo colormap

* add colormap image

* changed float value to avoid cast

* sorted flag check alphabetically

Add Matplotlib Perceptually Uniform Sequential colormaps (viridis, plasma, inferno, magma, cividis, twilight and twilight shifted).

* Rewrite polar transformations

- A new wrapPolar function encapsulate both linear and semi-log remap
- Destination size is a parameter or calculated automatically to keep objects size between remapping
- linearPolar and logPolar has been deprecated

* Fix build warning and error in accuracy test

* Fix function name to warpPolar

* Explicitly specify the mapping mode, so we retain all the parameters as non-optional.

Introduces WarpPolarMode enum to specify the mapping mode in flags

* resolves performance warning on windows build

* removed duplicated logPolar and linearPolar implementations

Added documentation to the Subdiv2D documentation, based on the previous
C API.

removed optim module; moved its functionality to core and photo modules; moved drawing functions from core to imgproc. Removed FilterEngine etc. from public API

- Wrote the documentation for the minEnclosingTriangle function (+1 extra picture depicting a sample output)

added pictures for OpenCV 2.x reference manual; fixed some build problems and done some more cleanup work