Adding support for user interface extensions.

Change-Id: I1e41d16efc11be31ad4c2fb0c09e86e3dfd26706
diff --git a/web/pom.xml b/web/pom.xml
index dc403b3..14545a9 100644
--- a/web/pom.xml
+++ b/web/pom.xml
@@ -136,6 +136,7 @@
                             com.fasterxml.jackson.databind.node,
                             com.google.common.base.*,
                             com.google.common.collect.*,
+                            com.google.common.io.*,
                             org.eclipse.jetty.websocket.*,
                             org.onlab.util.*,
                             org.onlab.osgi.*,