Added package.html and fixed cluster lists command output.
diff --git a/core/api/src/main/javadoc/org/onlab/onos/net/packet/package.html b/core/api/src/main/javadoc/org/onlab/onos/net/packet/package.html
new file mode 100644
index 0000000..c95ee9b
--- /dev/null
+++ b/core/api/src/main/javadoc/org/onlab/onos/net/packet/package.html
@@ -0,0 +1,4 @@
+<body>
+Mechanism for processing inbound packets intercepted from the data plane and
+for emitting outbound packets onto the data plane.
+</body>
\ No newline at end of file