Enable all GWT client permuations to be built by commenting out the lines that...

Enable all GWT client permuations to be built by commenting out the lines that specify specific clients.

appinventor/appengine/src/com/google/appinventor/YaClient.gwt.xml

@@ -5,8 +5,10 @@
 
   <!-- speed up compilation for testing. comment out the next two lines to compile 
        all permutations -->
+  <!--
   <inherits name='com.google.gwt.user.UserAgent'/>
   <set-property name="user.agent" value="safari,gecko1_8,ie6,ie8,ie9" />
+  -->
 
   <!-- inherits -->
   <inherits name="com.google.gwt.user.User" />