Fix edge case in stream tree
Fix edge case in stream tree

PingThingsIO/pt-mr-plotter,SoftwareDefinedBuildings/mr-plotter,SoftwareDefinedBuildings/mr-plotter,PingThingsIO/pt-mr-plotter,SoftwareDefinedBuildings/mr-plotter,PingThingsIO/pt-mr-plotter,PingThingsIO/pt-mr-plotter,SoftwareDefinedBuildings/mr-plotter,PingThingsIO/pt-mr-plotter,SoftwareDefinedBuildings/mr-plotter,SoftwareDefinedBuildings/mr-plotter,PingThingsIO/pt-mr-plotter,PingThingsIO/pt-mr-plotter