added service to provide canvas all over

src/app/app.component.html

@@ -85,6 +85,12 @@
         <option value="270">Links</option>
       </select>
     </div>
+    <div class="form-group">
+      <label class="form-control-label">
+        Knotenpunkte
+      </label>
+      <input type="number" class="form-control" formControlName="nodes" min="1" max="10">
+    </div>
     <button type="submit" class="btn btn-primary" [disabled]="configForm.invalid">Aktualisieren</button>
   </form>
 </aside>