- toggleVisibility() and toggleSelection() for legend entries

- use FontAwesomeModule also in app.module
- select and hide events in geomon-timeseries-chart.component.ts

src/app/components/legend-entry/legend-entry.component.ts

@@ -6,6 +6,8 @@ import { TimeInterval } from '../../../shared/models/timespan';
 import { DatasetApiService } from '../../services/dataset-api.service';
 import { InternalIdHandler, InternalDatasetId } from '../../../common/components/services/internal-id-handler.service';
 import { DatasetOptions } from '../../../shared/models/options';
+import { faEye, faEyeSlash } from '@fortawesome/free-solid-svg-icons';
+
 @Component({
     selector: 'geomon-legend-entry',
     templateUrl: './legend-entry.component.html',
@@ -18,6 +20,9 @@ export class LegendEntryComponent {
     @Output()
     public onSelectDate: EventEmitter<Date> = new EventEmitter();
 
+    faEye = faEye;
+    faEyeSlash= faEyeSlash;
+
     // public firstValue: FirstLastValue;
     // public lastValue: FirstLastValue;
     public hasData = true;