An object oriented finite state machine library based on UML state machines.
The objective of this library is to provide compact readable definitions
of complex state machines.

State Types Supported:
    Atomic:    Single state, actions defined as class methods
    Composite  Multiple Atomic states.  Transitions and actions determined
               by a state transition table. Only one state in composite is active at a time
    Parallel   Multiple parallel state machines. Events sent to paralel goes
               to all internal states.
 
Clock time of states may be made asynchronous to other states to support
simulation of systems with clock drift.
 
References:
    http://www.slideshare.net/erant/uml-statechart-diagrams

to do:
 - timers cancel function
 - clock reset effect on timer
 - add logging
 - clarify real-time versus simulated time
   make simulated a special setup
 - more unit tests