Fixes issue exposed by !4835.

vtkChartMatrix was setting sizes with negative widths/heights on
internal plots. This was happening during ParaView test playback.
Fixing vtkChartMatrix to avoid setting invalid sizes, prefer empty sizes
instead.

Added a few more assert checks in vtkContextClip and
vtkOpenGLContextDevice2D to catch such issues earlier.

vtkChartBox: replaced a retained, returned pointer with a stored
value.

vtkChartXY: Added check for range[0] == range[1] and avoid division by zero.

vtkFunctionParser: Added check for division of a vector by 0.0.

vtkUnstructuredGridQuadricDecimation: first time through loop,
lasterror is 0.0. Avoid division by zero by checking for 0.0.

vtkChartBox: replaced a retained, returned pointer with a stored
value.

vtkChartXY: Added check for range[0] == range[1] and avoid division by zero.

vtkFunctionParser: Added check for division of a vector by 0.0.

vtkUnstructuredGridQuadricDecimation: first time through loop,
lasterror is 0.0. Avoid division by zero by checking for 0.0.

vtkOpenGLContextDevice2D now respects tile-scale/tile-viewport in
`vtkOpenGLContextDevice2D::SetClip`. This addresses
paraview/paraview#18365.

Had to update TestChartUnicode baseline to get it passing.

vtkMath::Round converts double to int, as opposed to long.  Both can be lossy, but the former much more so.

Replaced some uses with std::round(), some with std::lround().

Eliminated the long->int truncation as much as possible, but kept it in many instances.

The new design for the VTK logo has been around for some time; this
patch set updates the testing data to match the new design.

Thanks to Steve Jordan and Dave DeMarle, the new VTK logos are now
available at:
https://www.vtk.org/download/

Related to !4334.

Beyond a certain zoom level, axes grid lines disappear.
This was due to a restriction of a maximum of 200
grid lines. This restriction has been removed.

The implementation of vtkChartXY::RecalculatePlotBounds() works with
either the scaled or unscaled bounds, depending on whether scaling is
enabled on the axis. However, the logic for handling the
AdjustLowerBoundForLogPlot flag was not correctly handling the case
where the bounds were log scaled.

To address this issue, the implementation now uses some logic to
determine whether log scaling is enabled and adjusts the bounds of the
plot accordingly.

Added a test for this feature as well.

PrintSelf() should print the member names and values. vtkAxis was
doing something different.

Make the following methods in vtkAxis virtual so users can customize vtkAxis:

GenerateSimpleLabel(), GenerateSprintfLabel(), GenerateLabelFormat(), GenerateLogSpacedLinearTicks()

This was originally proposed by a post on

http://vtk.1045678.n5.nabble.com/Request-Make-certain-methods-related-to-tick-labels-in-vtkAxis-virtual-td5744594.html

with the purpose of allowing the user to use customized axis labels, e.g. for displaying dates or times.

Apart from making the above methods virtual it is also required that the user can set the customized axis in a chart.
Hence further modifications were necessary in vtkChart, vtkChartXY and vtkChartXYZ to replace the axis created in the chart
by the customized axis.

Further a change was made to vtkAxis to allow the axis title to be switched off.

Found via `codespell -q 3 -I ../vtk-whitelist-words.txt --skip="./ThirdParty,./Utilities"`

Fix paraview/paraview#18076

Found via `codespell`

The rest of the test uses vtkNew, be consistent within the test. Removed
a C-style cast that was not needed.

Try to quickly clean up the dashboards

make image difference symmetric to catch some
failures that were slipping through. This exposed
a number of valid images that were no longer
correct and needed to be replaced.

Populate a script with `map_<md5>=<sha512>` variable settings and
then run the following to convert the content link files:

    git ls-files -- '*.md5' | while read f; do
      md5="$(cat "$f")"
      sha512="$(eval echo \${map_$md5})"
      rm "$f"
      echo $sha512 > ${f%.md5}.sha512
    done

This required some clean up, because the automatic changes borked a couple of files, but mostly resulted in stupid whitespacing. A few find/replace fixed things up.

There are now some duplicate semis because it did changes like:

  ~AMRIndexIterator() override{};
to
  ~AMRIndexIterator() override= default;;

Note there was a pointless semi before, which clang-tidy didn’t expect / account for.

My next commit will remove them.

If the user clicks in a plot that has an invalid (0,0) range, then in vtkContextScene::ProcessItem that is called after mouse events, the mapped mouse position becomes NaN, due to invalid matrix in the ContextScene's transform. This NaN position is then added to the function as a control point with an invalid NaN value. This fix makes sure this does not happen, by clamping the NaN values to minimum bounds on x axis, and 0 on y axis (any value comparison returns false if an operand is NaN, so need to check explicitly).

API improvement:

vtkAxis did not have an API to change minimum and maximum value
with one vtkChart::UpdateRange event.
This lead to inability to precisely shift an axis without temporarily
changing its range width (distance between minimum and maximum value),
and complexity and inefficiency when synchronizing axes
between multiple charts.

SetRange and SetUnscaledRange methods now invoke only one
vtkChart::UpdateRange event (after both minimum and maximum values
are updated).

Fixing minor issues:

1. Added a missing vtkCommand::InteractionEvent invocation
when vtkChartXY axes range are adjusted using ZoomAxis action
(this event indicates that the user adjusted axes and so the
application can propagate this change to other charts).

2. Fixed vtkChartXY transform computation logic

vtkChartXY unnecessarily recomputed transforms when axes
were modified after the chart's last modified timestamp.
ALso, vtkChartXY never recomputed transforms when chart
properties changed after axes changed, even when
recomputation would have been necessary.