Tells Rhino to display the notification modally.
RhinoCommon (in RhinoCommon.dll)
The notification will only be displayed if/once the instance is added to the NotificationCenter
Rhino keeps a queue of notifications that need to be shown modally, so calling this method does not mean that
this particular notification will be immediately displayed.
Rhino for WindowsSupported in: 6.1 BETA