New dashboard widgets

- Custom time range can now be picked
- Map now shows accuracy of latest beat
- Presets removed

frontend/src/app/app.module.ts

@@ -13,6 +13,7 @@ import { FilterComponent } from './filter/filter.component';
 import { LoginComponent } from './login/login.component';
 import { MapComponent } from './map/map.component';
 import { UserComponent } from './user/user.component';
+import { DashboardWidgetComponent } from './dashboard-widget/dashboard-widget.component';
 
 @NgModule({
   declarations: [
@@ -21,7 +22,8 @@ import { UserComponent } from './user/user.component';
     DashboardComponent,
     MapComponent,
     FilterComponent,
-    UserComponent
+    UserComponent,
+    DashboardWidgetComponent
   ],
   imports: [
     BrowserModule,