add date picker to dashboard page

pdb-js/src/app/dashboard-page/dashboard/dashboard.component.html

@@ -3,6 +3,16 @@
     width: 100%;
     height: 100%;
   }
+  .toolbar {
+    display: flex;
+    flex-direction: row;
+  }
+  .toolbar #filter-date-range{
+    flex-grow: 1;
+    display: flex;
+    align-items: center;
+    justify-content: flex-end;
+  }
   .center {
     position: absolute;
     top: 50%;
@@ -37,6 +47,9 @@
     flex-basis: 0;
     
   }
+  .editable {
+    padding: 0.5em;
+  }
 
   .editable-hovered {
     visibility: hidden;
@@ -73,12 +86,14 @@
     <button mat-button  (click)="addText()">Add Text</button>
     <button mat-button (click)="addPlot()">Add Plot</button>
     <button class="save-button" mat-button (click)="save()" [disabled]="!isDirty()">Save</button>
+    <div id="filter-date-range">
+      Date range: <app-date-picker #datePicker (dateValueSelected)="updateDateRange($event)" ></app-date-picker>
+    </div>
   </div>
   <div class="editable">
     <h1>{{dashboard.name}}<button mat-icon-button (click)="editNameAndDescription()" class="editable-hovered"><img src="/assets/img/edit-outline.svg"/></button></h1>
     <p>{{dashboard.description}}</p>
   </div>
-
   <div cdkDropListGroup class="dashboard-area">
     <div 
       cdkDropList