Add "Clear all" button

src/main/webapp/app/search/metadata/metadata.component.html

 <div class="solid" [hidden]="frequencies == null">
     <span class="meta" jhiTranslate="search.metadata.{{parameter}}">file format</span>
+    <span class="clear" float="right" jhiTranslate="search.metadata.clearLocalFilters"
+        (click)="clearFilters()"
+    >clear all</span>
     <li class="meta" *ngFor="let frequency of frequencies"
         (click)="toggleSelection(parameter, frequency.key)"
         [style.background-color]="isSelected(frequency.key) ? 'rgba(0,255,0,0.5)' : 'rgba(0,0,0,0)'">
@@ -8,6 +11,5 @@
                 <span class="count">{{frequency.value}}</span>
             </a>
         </div>
-
     </li>
 </div>

src/main/webapp/app/search/metadata/metadata.component.ts

@@ -28,4 +28,8 @@ export class MetadataComponent {
   isSelected(name: string): boolean {
     return this.selectedItems.has(name);
   }
+
+  clearFilters(): void {
+    this.selectedItems = new Set();
+  }
 }

src/main/webapp/app/search/metadata/metadata.scss

 li.meta:hover {
-  background-color: #CACACA;
+  background-color: #cacaca;
 }
 li.meta {
   list-style-type: none;
@@ -23,3 +23,12 @@ div.solid {
   border-color: rgb(223, 226, 230);
   margin-bottom: 20px;
 }
+span.clear {
+  float: right;
+  padding-left: 10px;
+  padding-right: 10px;
+  cursor: pointer;
+}
+span.clear:hover {
+  background-color: rgba(0, 0, 0, 0.1);
+}

src/main/webapp/i18n/de/search.json

@@ -5,6 +5,7 @@
     "usage": "Die Suchmaske erlaubt es aufbauend auf diversen Suchkriterien (z.B. Volltextsuche, Programmiersprachen, Schlüsselwörter usw.) nach Volltexten in der Sharing Plattform zu suchen. In der Suchmaske für Volltexte können boolsche Operatoren verwendet werden. Abgesehen von der Volltextsuche sind keine weitern Felder angegeben werden.",
     "metadata": {
       "filter": "Suchfilter",
+      "clearLocalFilters": "Alle löschen",
       "information": "Suchinformation",
       "fileFormat": "Dateiformat",
       "repository": "Repository",

src/main/webapp/i18n/en/search.json

@@ -5,6 +5,7 @@
     "usage": "The search mask allows you to search for full texts in the sharing platform based on various search criteria (e.g. full text search, programming languages, keywords, etc.). Boolean operators can be used in the search mask for full texts. Apart from the full text search, no further fields are to be specified.",
     "metadata": {
       "filter": "Search filter",
+      "clearLocalFilters": "Clear all",
       "information": "Search information",
       "fileFormat": "File format",
       "repository": "Repository",