Remove deprecated @App decorator
Remove deprecated @App decorator

- Update Readme to remove [deprecated @App usage](https://github.com/driftyco/ionic/blob/2.0/CHANGELOG.md#200-beta8-2016-06-06)
- Remove config property as per [the beta 8 upgrade
  guide](https://github.com/driftyco/ionic/blob/2.0/CHANGELOG.md#steps-to-upgrade-to-beta-8)

Verurteilt/core,ngx-translate/core,ocombe/ng2-translate,ocombe/ng2-translate,ngx-translate/core,Verurteilt/core