Work towards #123 adaptive bitrate

components/common/cpp/include/ftl/timer.hpp

components/net/cpp/include/ftl/net/peer.hpp

components/net/cpp/include/ftl/net/universe.hpp

components/net/cpp/src/universe.cpp

components/rgbd-sources/CMakeLists.txt

components/rgbd-sources/include/ftl/rgbd/detail/abr.hpp

components/rgbd-sources/include/ftl/rgbd/detail/netframe.hpp

components/rgbd-sources/include/ftl/rgbd/streamer.hpp

components/rgbd-sources/src/abr.cpp

components/rgbd-sources/src/bitrate_settings.hpp

components/rgbd-sources/src/net.cpp

components/rgbd-sources/src/net.hpp

components/rgbd-sources/src/streamer.cpp