Channels added to the design

src/adt2amas.cpp

src/amas/CMakeLists.txt

src/amas/action.cpp

src/amas/action.hpp

src/amas/automata.cpp

src/amas/automata.hpp

src/amas/automaton.cpp

src/amas/automaton.hpp

src/amas/channel.cpp

src/amas/channel.hpp

src/amas/channel_type.cpp

src/amas/label.cpp

src/amas/label.hpp

src/amas/state.cpp

src/amas/state.hpp

src/amas/synchronization.cpp

src/amas/synchronization.hpp

src/amas/synchronization_type.cpp

src/amas/synchronization_type.hpp

src/amas/transition.cpp