- add "moment": "^2.29.1" and "chartjs-adapter-moment": "^1.0.0",

- add core module for time.service.ts
- add interfaces for timespan.ts an dataset.ts

src/common/core/core.module.ts

@@ -0,0 +1,19 @@
+import { CommonModule } from '@angular/common';
+import { NgModule } from '@angular/core';
+
+
+import { DatasetApiService } from '../../app/services/dataset-api.service';
+
+
+@NgModule({
+  imports: [    
+    CommonModule
+  ],
+  declarations: [
+  ],  
+  exports: [ 
+  ],
+  providers: [      
+  ]
+})
+export class CoreModule { }