Start all components on component map.

def start_system(components, bind_to, hooks={}):
    """Start all components on component map."""
    deps = build_deps_graph(components)
    started_components = start_components(components, deps, None)

    run_hooks(hooks, started_components)

    if type(bind_to) is str:
        master = started_components[bind_to]
    else:
        master = bind_to

    setattr(master, '__components', started_components)
    return master