Add fmPackageExists directive

src/app/test/test.component.html

@@ -2,7 +2,7 @@
     <div class="row">
         <fm-gradient-select [gradientItems]="gradientItems|async" [showLabel]="false" [showAdd]="true"></fm-gradient-select>
     </div>
-    <div class="row mt-3">
+    <div class="row mt-3" *fmPackageExists="'vnd.farmmaps.itemtype.package.dacom'">
         <button class="btn btn-primary" (click)="onTest($event)">Test</button>
     </div>
 </div>