Updates the classpath of apichecker in the build.xml file as per r5048 commit

Patch by: amitmanjhi



git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@5055 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/build.xml b/build.xml
index 15ea822..cd9b583 100755
--- a/build.xml
+++ b/build.xml
@@ -97,6 +97,7 @@
         <pathelement location="${gwt.build.out}/dev/core/bin"/>
         <pathelement location="${gwt.build.out}/user/bin"/>
         <pathelement location="${gwt.tools.lib}/eclipse/jdt-3.3.1.jar"/>
+        <pathelement location="${gwt.tools.lib}/tomcat/commons-collections-3.1.jar"/>
         <pathelement path="${java.class.path}"/>
       </classpath>
       <arg value="-configFile"/>