Fixing javadocs and adding missing package javadocs.
Also marked a few packages and classes as deprecated.

Change-Id: I8629ad001f218f92c35721daa3b7c0ebe0916c27
diff --git a/core/api/src/main/java/org/onlab/onos/net/Link.java b/core/api/src/main/java/org/onlab/onos/net/Link.java
index cce34fa..f091dc4 100644
--- a/core/api/src/main/java/org/onlab/onos/net/Link.java
+++ b/core/api/src/main/java/org/onlab/onos/net/Link.java
@@ -94,13 +94,15 @@
 
     /**
      * Returns the link state.
+     *
+     * @return link state
      */
     State state();
 
     /**
      * Indicates if the link is to be considered durable.
      *
-     * @return link state
+     * @return true if the link is durable
      */
     boolean isDurable();