Update GWT to 2.1.1

Change-Id: Ief89db54d54b44e91e61dd6f548cb09f0908a176
diff --git a/pom.xml b/pom.xml
index 59efaf1..09ceba6 100644
--- a/pom.xml
+++ b/pom.xml
@@ -253,7 +253,7 @@
   </licenses>
 
   <properties>
-    <gwtVersion>2.0.0</gwtVersion>
+    <gwtVersion>2.1.1</gwtVersion>
     <project.build.sourceEncoding>
       UTF-8
     </project.build.sourceEncoding>