Add web offscreen plots

src/main.cpp

src/mainoffscreenplot.cpp

src/mainplot.cpp

src/manager/OffScreenPlotManager.cpp

src/manager/OffScreenPlotManager.h

src/manager/RequestDealerManager.cpp

src/manager/ServerSubscriberManager.cpp

src/plot/Plot2D.cpp

src/plot/Plot2D.h

src/plot/PlotWindow.cpp

src/plot/offscreen/OffScreenEmptyPlot.cpp

src/plot/offscreen/OffScreenEmptyPlot.h

src/plot/offscreen/OffScreenPlot.h

src/plot/offscreen/OffScreenPlot1D.cpp

src/plot/offscreen/OffScreenPlot1D.h

src/plot/offscreen/OffScreenPlot2D.cpp

src/plot/offscreen/OffScreenPlot2D.h

src/plot/property/PropertyPlot2D.cpp

src/plot/property/PropertyPlot2D.h

src/view/mpl/MplPlot2D.cpp