Merge topic 'fix-clamping'

9c6c952e vtkPiecewiseFunction: actually assign a fallback SearchMethod
2e9d08b6 vtkImageToStructuredPoints: fix improper bounds alignment
8f114753 vtkPostgreSQLDatabase: factor out clamping
aad39093 Interaction/Widgets: clamp RepresentationState first
e14e3a4a vtkAxis: fix clamping assignment
e641ea55 vtkImplicitModeller: factor out clamping
ac81ee5c vtkSelectionSource: factor out clamping
80c48cd5 vtkCamera: clamp ViewAngle before updating

Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Reviewed-by: David Thompson <david.thompson@kitware.com>
Merge-request: !11892