Revert changes from PR #173.
Revert changes from PR #173.

benelliott/angular2-select,basvandenberg/angular2-select,basvandenberg/ng-select,basvandenberg/ng-select,benelliott/angular2-select,basvandenberg/angular2-select,basvandenberg/angular2-select,basvandenberg/ng-select,benelliott/angular2-select,basvandenberg/ng-select,benelliott/angular2-select