Add doc and license to SDK

SDK/C++/private/observer_impl.cpp

SDK/C++/public/LICENSE

SDK/C++/public/README.md

SDK/C++/public/include/voltu/defines.hpp

SDK/C++/public/include/voltu/feed.hpp

SDK/C++/public/include/voltu/initialise.hpp

SDK/C++/public/include/voltu/observer.hpp

SDK/C++/public/include/voltu/opencv.hpp

SDK/C++/public/include/voltu/operator.hpp

SDK/C++/public/include/voltu/pipeline.hpp

SDK/C++/public/include/voltu/room.hpp

SDK/C++/public/include/voltu/system.hpp

SDK/C++/public/include/voltu/types/channel.hpp

SDK/C++/public/include/voltu/types/errors.hpp

SDK/C++/public/include/voltu/types/frame.hpp

SDK/C++/public/include/voltu/types/image.hpp

SDK/C++/public/include/voltu/types/intrinsics.hpp

SDK/C++/public/include/voltu/types/pointcloud.hpp

SDK/C++/public/include/voltu/types/property.hpp

SDK/C++/public/include/voltu/voltu.hpp