docs: add play instructions
docs: add play instructions

donniewa/angular2-routing-example,donniewa/angular2-routing-example,kanvaz/kanvaz-app,ideadapt/angular2-experiments,kanvaz/kanvaz-app,donniewa/angular2-routing-example,ideadapt/angular2-experiments,kanvaz/kanvaz-app,ideadapt/angular2-experiments