Added javadoc for all the helper classes in SDN-IP.

Also changed a couple of names to better reflect the usage or comply with
naming standards:
  in IBgpRouteService.java: getBGPdRestIp -> getBgpdRestIp
  in Prefix.java: MAX_BYTES -> ADDRESS_LENGTH

Change-Id: Id23b6bb077d79d671d21e2490ab410f322d7c166
diff --git a/src/main/java/net/onrc/onos/apps/bgproute/RibUpdate.java b/src/main/java/net/onrc/onos/apps/bgproute/RibUpdate.java
index 58ebdf1..3f74a08 100644
--- a/src/main/java/net/onrc/onos/apps/bgproute/RibUpdate.java
+++ b/src/main/java/net/onrc/onos/apps/bgproute/RibUpdate.java
@@ -1,29 +1,72 @@
 package net.onrc.onos.apps.bgproute;
 
+/**
+ * Represents a route update received from BGPd. An update has an operation
+ * describing whether the update is adding a route or revoking a route. It also
+ * contains the route prefix, and {@link RibEntry} containing next hop and
+ * sequence number information for the update.
+ */
 public class RibUpdate {
     private final Operation operation;
     private final Prefix prefix;
     private final RibEntry ribEntry;
 
+    /**
+     * Updates can either add new routes or revoke old routes. The
+     * {@link Operation} enum descibes which action is being taken.
+     */
     public enum Operation {
+        /**
+         * Represents a route update. ONOS should update its route information
+         * for this prefix to the new information provided in this
+         * {@link RibUpdate}. This means either add a new prefix, or update
+         * the information for an existing prefix.
+         */
         UPDATE,
+        /**
+         * Represents a route delete. ONOS should remove this prefix and route
+         * information from its route table.
+         */
         DELETE
     }
 
+    /**
+     * Class constructor, taking the operation of the update, the route prefix
+     * and the {@link RibEntry} describing the update.
+     *
+     * @param operation the operation of the update
+     * @param prefix the route prefix
+     * @param ribEntry the update entry
+     */
     public RibUpdate(Operation operation, Prefix prefix, RibEntry ribEntry) {
         this.operation = operation;
         this.prefix = prefix;
         this.ribEntry = ribEntry;
     }
 
+    /**
+     * Gets the operation of the update.
+     *
+     * @return the operation
+     */
     public Operation getOperation() {
         return operation;
     }
 
+    /**
+     * Gets the route prefix of the update.
+     *
+     * @return the prefix
+     */
     public Prefix getPrefix() {
         return prefix;
     }
 
+    /**
+     * Gets the {@link RibEntry} of the update.
+     *
+     * @return the entry
+     */
     public RibEntry getRibEntry() {
         return ribEntry;
     }