uriMappings for installed plugins

plugins/org.yakindu.sct.model.sgen/plugin.xml

@@ -16,5 +16,12 @@
             class="org.yakindu.sct.model.sgen.SGenPackage"
             genModel="model/emf/sgen.genmodel"/>
    </extension>
+   <extension
+         point="org.eclipse.emf.ecore.uri_mapping">
+      <mapping
+            source="platform:/resource/org.yakindu.sct.model.sgen/model/emf/sgen.ecore"
+            target="model/emf/sgen.ecore">
+      </mapping>
+   </extension>
 
 </plugin>