React Router 2 Exercise: https://github.com/C4Q/AC_4_Web/blob/c2f978e073896fd340cd98c6aaf9d0ad0043d963/units/react/projects/react_router_2/react_router_2.md
React Router with State Exercise: https://github.com/C4Q/AC_4_Web/blob/master/units/react/projects/react_routes_and_state/react_routes_and_state.md