def apply(event_name, silent = false)
      define_event_transition(event_name, silent)
      define_event_bang(event_name, silent)
    end
def apply(event_name, silent = false)
      define_event_transition(event_name, silent)
      define_event_bang(event_name, silent)
    end
Initialize an EventDefinition

 @param [StateMachine] machine

 @api private
 Define transition event names as state machine events

 @param [Symbol] event_name
   the event name for which definition is created

 @return [nil]

 @api public