Avoid checking UUID at server if app is online

src/components/LoginSystem.vue

@@ -271,7 +271,14 @@ export default {
   },
   mounted() {
     this.CONST_URL_DOMAIN = CommonUtil.CONST_URL_DOMAIN;
-    this.checkValidUUID();
+	if(navigator.onLine) 
+	{
+    	this.checkValidUUID();
+	}
+	else
+	{
+		this.getUserFromStorage();
+	}
   },
 };
 </script>