message: fix(dropdown): Add missing rxjs filter operator dependency
diff: @@ -3,6 +3,7 @@ import {
  Renderer, ViewContainerRef
  } from '@angular/core';
  import { Subscription } from 'rxjs/Subscription';
  +import 'rxjs/add/operator/filter';
  import { ComponentLoader, ComponentLoaderFactory } from '../component-loader';
  import { BsDropdownConfig } from './bs-dropdown.config';
  