Move OpenGl_Structure::myZLayer to base class Graphic3d_CStructure.
Graphic3d_ZLayerId - introduce new pre-defined ZLayers.
Do not clear Depth buffer twice for default ZLayer.
AIS_InteractiveContext::Display() - add new argument AIS_DisplayStatus to specify displaying status.
Drop unused Graphic3d_CPick and related methods.
Drop OpenGl_Structure::myNamedStatus - use flags from parent class Graphic3d_CStructure directly.
OpenGl_LayerList ::ChangeLayer(), ::ChangePriority - fix structure remove from unexpected layer.
Merge class OpenGl_PriorityList into OpenGl_Layer.
PrsMgr_PresentationManager::mySelectionColor - store selection color as field of Presentation Manager.
PrsMgr_Presentation class - do not declare private methods as virtual.
PrsMgr_Presentation::Highlight() - extend method syntax and drop methods ::Color() and ::BoundBox().
PrsMgr_PresentableObject - store ZLayer in presentable object
to display object presentations in required layer directly
(without displaying it in wrong layer first).
test/mesh/end - force re-displaying the shape to compute mesh anew
Test-case for issue
