fix(datepicker): If the date was set by ngModel it will be overwritte…

…n by default value

When ngModel was set only the activeDate always got reset to the current date.

components/datepicker/datepicker-inner.ts

@@ -126,7 +126,7 @@ export class DatePickerInner implements OnInit {
 
  if (this.initDate) {
  this.activeDate = this.initDate;
- } else {
+ } else if (this.activeDate === undefined) {
  this.activeDate = new Date();
  }
  this.selectedDate = new Date(this.activeDate.valueOf());