Add examples CoinViewer, RGBOffscreenRendering, DepthOffscreenRendering

VirtualRobot/examples/CMakeLists.txt

VirtualRobot/examples/CoinViewer/CMakeLists.txt

VirtualRobot/examples/CoinViewer/CoinViewer.cpp

VirtualRobot/examples/CoinViewer/CoinViewer.h

VirtualRobot/examples/CoinViewer/CoinViewer.ui

VirtualRobot/examples/CoinViewer/main.cpp

VirtualRobot/examples/DepthOffscreenRendering/CMakeLists.txt

...mples/DepthOffscreenRendering/DepthOffscreenRendering.cpp

...xamples/DepthOffscreenRendering/DepthOffscreenRendering.h

...amples/DepthOffscreenRendering/DepthOffscreenRendering.ui

VirtualRobot/examples/DepthOffscreenRendering/main.cpp

VirtualRobot/examples/RGBOffscreenRendering/CMakeLists.txt

.../examples/RGBOffscreenRendering/RGBOffscreenRendering.cpp

...ot/examples/RGBOffscreenRendering/RGBOffscreenRendering.h

...t/examples/RGBOffscreenRendering/RGBOffscreenRendering.ui

VirtualRobot/examples/RGBOffscreenRendering/main.cpp