QVTKOpenGLWidget fixes
This add some QVTKOpenGLWidget related fixes :
- Correctly parent all pqPropertyWidget
- Fix cursor issue reported by @utkarsh.ayachit
- Ensure QVTKOpenGLWidget can be replaced by QVTKOpenGLSimpleWidget
- Fix some size issues in pqQVTKWidgetEventTranslator
- Update VTK to bring in many QVTK related fixes.
Edited by Mathieu Westphal (Kitware)