feat: Allow select number of clusters

Add input for number of clusters and
pass this to the rural-attractiveness service

src/adjuster/adjuster.directive.html

@@ -7,6 +7,10 @@
       <div class="text-warning pt-2" [hidden]="!noDataSelected()">Select at least one dataset and set at least one
         factor's weight to a non-zero value.</div>
     </div>
+    <div class="p-2 center-block">
+      <div class="pt-2 text-secondary">Number of clusters to create: {{adjusterService.numberOfClusters}}</div>
+      <input type="range" class="custom-range" [(ngModel)]="adjusterService.numberOfClusters" min="5" max="15" step="1">
+    </div>
     <div *ngFor="let factor of adjusterService.factors; let datasetlistVisible = false">
       <div class="d-flex flex-row">
         <div class="p-2 flex-grow-1">

src/adjuster/adjuster.service.ts

@@ -15,6 +15,7 @@ export class AdjusterService {
   serviceBaseUrl: string;
   factors = [];
   clusters = [];
+  numberOfClusters = 12;
   method: string;
   methods = [
     {
@@ -120,6 +121,7 @@ export class AdjusterService {
       this._clusteringInProcess = true;
       this.httpClient
         .post(this.serviceBaseUrl + 'clusters', {
+          numberOfClusters: this.numberOfClusters,
           factors: this.factors.map((f) => {
             return {
               factor: f.name,