Javadoc improvements
diff --git a/utils/netty/src/main/java/org/onlab/netty/package-info.java b/utils/netty/src/main/java/org/onlab/netty/package-info.java
new file mode 100644
index 0000000..b1b90a3
--- /dev/null
+++ b/utils/netty/src/main/java/org/onlab/netty/package-info.java
@@ -0,0 +1,4 @@
+/**
+ * Asynchronous messaging APIs implemented using the Netty framework.
+ */
+package org.onlab.netty;
\ No newline at end of file