Release Name: v1.2.0_macOS

A feature as been asked : being able to choose the range of your colorbar. This feature implies that we add a range relative to each attribute/colorbar, that the user could modify, and reset to the common Range, which is the actual real range we used to use.
This new version is also way faster, optimizing the number of times the multiple rendering are called.

- A structure as been created, colorBarStruct, to replace the colorPointList. This ColorBar contains a colorPointList and a range, that we will load like we used to do with the colorpoints.Now the range does not automatically adapt to the selected meshes.
- deleted removeArrow() in gradientWidget
- added the bool variable m_updateOnPositionChanged in ShapePopulationQT to avoid unecessary updates when a color arrow is moved
- the bool variable m_updateOnAttributeChanged helps not calling the spinBox_Attribute_indexChanged() when adding every attribute during the createWidget() function
- setting the scrollArea (Display Area) visibility to false when creating widgets, then setting it to true at the end (after placing and resizing) will only render everything at the end.
- added the bool variable m_renderAllSelection in ShapePopulationBase to avoid calling RenderSelection() for nothing. To allow the renderselection when interacting with the mouse, we created two observers on BeginInteraction and EndInteraction on the Interactor, which will respectively set m_renderAllselection to true and false.
- Changed loadVTKfileCLP into loadVTKfilesCLP, so that using CLP or Drag&Drop, createWidgets is only called once all the files are added to the list
- in createWidgets, anytime new vtk are added, the synchronization is set to Delayed, to avoid frozing the software if there are too much points to process.
- when loading on drag&drop, does not apply to all attributes anymore but only the active one (workaround to not change the chosenRange to all the attributes ranges).