0.18.0

• breaking change Router now only prefetches async state (via react-async)
  if and only if current handler's type is different from next handler's type.

  This now matches the behaviour of getInitialState which is only called once
  for each component instance.

  If you have your async state dependent on props, you need to initiate async
  state update in componentWillReceiveProps(nextProps) by using values from
  nextProps.