Add a bullet point linking to angular.io/dart on the README.
Add a bullet point linking to angular.io/dart on the README.

Closes https://github.com/dart-lang/angular2/issues/6.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=133265762

chalin/angular2,angulardart/angular,angulardart/angular,kevmoo/angular,matanlurey/angular,angulardart/angular,kevmoo/angular,chalin/angular2,matanlurey/angular,matanlurey/angular,chalin/angular2,kevmoo/angular