Enable checkstyle Javadoc Comment Style rule

Turn on the Javadoc Comment Style rule and fix
any violations that come up.  This is related to
requiring javadoc description comments to end
with a '.'

Change-Id: I19cf1b9f00d3040987e0b4c8b39461e2e0ad66b5
diff --git a/src/main/java/net/onrc/onos/core/packet/IPacket.java b/src/main/java/net/onrc/onos/core/packet/IPacket.java
index 8f31960..9cbba4d 100644
--- a/src/main/java/net/onrc/onos/core/packet/IPacket.java
+++ b/src/main/java/net/onrc/onos/core/packet/IPacket.java
@@ -18,7 +18,7 @@
 package net.onrc.onos.core.packet;
 
 /**
- * @author David Erickson (daviderickson@cs.stanford.edu)
+ * @author David Erickson (daviderickson@cs.stanford.edu).
  */
 public interface IPacket {
     /**
@@ -44,20 +44,20 @@
     public IPacket setParent(IPacket packet);
 
     /**
-     * Reset any checksums as needed, and call resetChecksum on all parents
+     * Reset any checksums as needed, and call resetChecksum on all parents.
      */
     public void resetChecksum();
 
     /**
      * Sets all payloads parent packet if applicable, then serializes this
-     * packet and all payloads
+     * packet and all payloads.
      *
      * @return a byte[] containing this packet and payloads
      */
     public byte[] serialize();
 
     /**
-     * Deserializes this packet layer and all possible payloads
+     * Deserializes this packet layer and all possible payloads.
      *
      * @param data
      * @param offset offset to start deserializing from