Use a master controller for all Plan elements

qgroundcontrol.pro

src/FlightDisplay/FlightDisplayView.qml

src/FlightDisplay/FlightDisplayViewMap.qml

src/FlightMap/Widgets/MapFitFunctions.qml

src/JsonHelper.cc

src/JsonHelper.h

src/MissionManager/GeoFenceController.cc

src/MissionManager/GeoFenceController.h

src/MissionManager/MissionController.cc

src/MissionManager/MissionController.h

src/MissionManager/PlanElementController.cc

src/MissionManager/PlanElementController.h

src/MissionManager/PlanMasterController.cc

src/MissionManager/PlanMasterController.h

src/MissionManager/RallyPointController.cc

src/MissionManager/RallyPointController.h

src/PlanView/MissionItemEditor.qml

src/PlanView/PlanToolBar.qml

src/PlanView/PlanView.qml

src/QGCApplication.cc