add date range field

It is (again) surprisingly hard to find a decent date+time-range
picker that works with Angular. Daterangepicker, which I used with
my VueJS application does not work with Angular. I can't get the
angularized version
https://github.com/fragaria/angular-daterangepicker) to work either.
And and a native Angular date picker
(https://github.com/GNURub/ngx-daterangepicker) doesn't work either.

pdb-js/src/app/visualization-page/visualization-page.component.ts

@@ -11,6 +11,8 @@ import { FormControl } from '@angular/forms';
 })
 export class VisualizationPageComponent implements OnInit {
   
+  dateRange = new FormControl('2019-10-05 00:00:00 - 2019-10-11 23:59:59');
+  
   availablePlotTypes = {};
   
   selectedPlotType = new FormControl('');