title: Create a timeout in an SCXML state machine
body: <p>In an <a href="http://www.w3.org/TR/scxml/" rel="noreferrer">SCXML</a> state machine, how can I say <em>"Fire an event 3 minutes after I enter this state, but not if I sit in the state for 2.9 minutes and then leave. If I re-enter the state, restart the timer (don't go off in 0.1 minutes)"</em></p>