Initial implementation of state machines defined using greenery.fsa
o Added git@github.com:pjkundert/greenery.git 'develop' branch submodule
o Added cpppo.dfa 'name' to constructor, defaulting to class name
o cpppo.fsm subclasses dfa, taking a regex or greenery.lego/fsm as
  input, and converts it to an equivalent state machine of state_input
  nodes.
o Allow multiple transitions into a terminal state; terminate only
  when no more transitions available.
o Unit test using a regular expression to define state machine