message: Updated nav react mobile readme to component api
diff: ```jsx
  import { StateNavigator } from 'navigation';
  import { NavigationHandler, NavigationLink, NavigationBackLink } from 'navigation-react';
  -import { NavigationMotion } from 'navigation-react-mobile';
  +import { NavigationMotion, Scene } from 'navigation-react-mobile';
  const stateNavigator = new Navigation.StateNavigator([
  { key: 'hello', route: '' },
  { key: 'world', trackCrumbTrail: true }
  ]);
  +stateNavigator.start();
  +
  const Hello = () => (
  <NavigationLink stateKey="world">
  Hello
  @@ -22,28 +24,22 @@ const World = () => (
  </NavigationBackLink>
  );
  -const { hello, world } = stateNavigator.states;
  -
  -hello.renderScene = () => <Hello />;
  -world.renderScene = () => <World />;
  -
  -stateNavigator.start();
  -
  -ReactDOM.render(
  +const App = () => (
  <NavigationHandler stateNavigator={stateNavigator}>
  <NavigationMotion
  unmountedStyle={{ translate: 100 }}
  mountedStyle={{ translate: 0 }}
  - crumbStyle={{ translate: -10 }}>
  - {(style, scene, key) => (
  + crumbStyle={{ translate: -10 }}
  + renderMotion={(style, scene, key) => (
  <div
  key={key}
  style={{ transform: `translate(${style.translate}%)` }}>
  {scene}
  </div>
  - )}
  + )}>
  + <Scene stateKey="hello"><Hello /></Scene>
  + <Scene stateKey="world"><World /></Scene>
  </NavigationMotion>
  - </NavigationHandler>,
  - document.getElementById('root')
  + </NavigationHandler>
  );
  ```
  \ No newline at end of file
  