message: Returned mounted or crumb style based on mount
  State initiailsed in constuctor using enter. There can be crumbs for initial render and these should get crumb style. Otherwise the first render on client animates from mounted to crumb on mount
diff: @@ -108,7 +108,7 @@ class NavigationMotion extends React.Component<any, any> {
  <Motion
  data={this.getScenes()}
  getKey={({key}) => key}
  - enter={({state, data}) => this.getPropValue(oldState ? unmountedStyle : mountedStyle, state, data)}
  + enter={({mount, state, data}) => this.getPropValue(oldState ? unmountedStyle : (mount ? mountedStyle : crumbStyle), state, data)}
  update={({mount, state, data}) => this.getPropValue(mount ? mountedStyle : crumbStyle, state, data)}
  leave={({state, data}) => this.getPropValue(unmountedStyle, state, data)}
  duration={duration}
  