message: docs(popover): add demo for toggle method in Manual triggering demo
  Add demo for toggle method from directive
  Close
diff: <button type="button" class="btn btn-warning" (click)="pop.hide()">
  Hide
  </button>
  +<button type="button" class="btn btn-info" (click)="pop.toggle()">
  + Toggle
  +</button>
  