Update net code file structure

net/README.md

net/cpp/CMakeLists.txt

net/cpp/include/ftl/net.hpp

net/cpp/include/ftl/net/dispatcher.hpp

net/cpp/include/ftl/net/func_traits.hpp

net/cpp/include/ftl/net/handlers.hpp

net/cpp/include/ftl/net/ice.hpp

net/cpp/include/ftl/net/listener.hpp

net/cpp/include/ftl/net/p2p.hpp

net/cpp/include/ftl/net/protocol.hpp

net/cpp/include/ftl/net/socket.hpp

net/cpp/include/ftl/net/stun.hpp

net/cpp/include/ftl/uri.hpp

net/cpp/include/ftl/uuid.hpp

net/cpp/src/dispatcher.cpp

net/cpp/src/ice.cpp

net/cpp/src/listener.cpp

net/cpp/src/main.cpp

net/cpp/src/net.cpp

net/cpp/src/p2p.cpp