Add support for -h flag
Add support for -h flag

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