Replaced context menu on PipingSurfaceLineCollectionNodePresenter with one constructed through ContextMenuBuilder. GuiContextMenuItemFactory now only requires the IGuiCommandHandler for constructing. Implemented CanExportFromGuiSelection and CanShowPropertiesForGuiSelection on GuiCommandHandler to determine menu item state. Related to Issue [WTI-172] git-svn-id: https://repos.deltares.nl/repos/WettelijkToetsInstrumentarium/trunk@1029 5a3db67b-de53-47b5-99c8-a1c30a6650e2