Added tests

Change-Id: I493675212f4b1548b32a6d92ce3664d184bc0e04
diff --git a/src/app/core/services/navigation.ts b/src/app/core/services/navigation.ts
index 8cb3b66..04eb575 100644
--- a/src/app/core/services/navigation.ts
+++ b/src/app/core/services/navigation.ts
@@ -26,6 +26,9 @@
   }
 
   add(route: IXosNavigationRoute) {
+    if (angular.isDefined(route.state) && angular.isDefined(route.url)) {
+      throw new Error('[XosNavigation] You can\'t provide both state and url');
+    }
     this.routes.push(route);
   }
 }