message: feat(sortable): add aria attributes
  Closes
diff: @@ -39,6 +39,8 @@ import { DraggableItemService } from './draggable-item.service';
  (dragend)="resetActiveItem($event)"
  (dragover)="onItemDragover($event, i)"
  (dragenter)="cancelEvent($event)"
  + aria-dropeffect="move"
  + [attr.aria-grabbed]="i === activeItem"
  ><ng-template [ngTemplateOutlet]="itemTemplate || defItemTemplate"
  [ngTemplateOutletContext]="{item:item, index: i}"></ng-template></div>
  </div>
  @@ -56,7 +58,6 @@ import { DraggableItemService } from './draggable-item.service';
  /* tslint:enable */
  export class SortableComponent implements ControlValueAccessor {
  private static globalZoneIndex = 0;
  -
  /** field name if input array consists of objects */
  @Input() fieldName: string;
  