simplify:
- use same html file for dart and JS
- build benchmarks automatically when doing `gulp build`
- centralize configuration
modularize:
- move all build tasks into separate node.js modules under
`tools/build`.
changes:
- the `build` folder is now the `dist` folder
Closes#284
- Allow to access containing component directive instance from the shadow DOM.
- Allow to access app services of the app level injector of the component
when the component is instantiated.