png images were truncated when ROOT was running in a small screen attached to the Mac with the graphics window on the the Mac display.

It was reported [here](https://root-forum.cern.ch/t/tcanvas-print-png-outputs-fraction-of-figure-when-canvas-size-is-declared/26011/44).
Thanks Timur to have found this fix.

thanks to Enrico for providing most of the text.

It was reported here:
https://root-forum.cern.ch/t/th1-setoption-method-not-working-when-called-from-th3d-instance/26227

When the F and L options are combined to draw a TGraph, a filled polygon AND a line plot are produced.

thanks Enrico for the help.

 It is now fixed. It was reported here: https://sft.its.cern.ch/jira/browse/ROOT-8200

This was described here:
    https://root-forum.cern.ch/t/set-logscale-on-z-axis-in-2d-histo/25385

Too many user-visible side-effects!
This reverts commit 0ad637e2.

Too many user-visible side-effects!
This reverts commit c9d347c0.

    -  LogZ for violins
    -  scaling of candles and violins with respect to each other
    -  static functions for WhiskerRange and BoxRange

New method `TColor::SetColorThreshold(Float_t t)` to specify the color threshold used by GetColor to retrieve a color.

  The top color becomes bottom and vice versa. This was suggested by Karl Smith here: https://root-forum.cern.ch/t/inverted-color-palettes/24826/2.