Cleaned up a slew of Javadoc errors in preparation for switch over to Java 8.
diff --git a/core/api/src/main/java/org/onlab/onos/net/SparseAnnotations.java b/core/api/src/main/java/org/onlab/onos/net/SparseAnnotations.java
index abe6cd1..6487d96 100644
--- a/core/api/src/main/java/org/onlab/onos/net/SparseAnnotations.java
+++ b/core/api/src/main/java/org/onlab/onos/net/SparseAnnotations.java
@@ -25,8 +25,9 @@
 
     /**
      * {@inheritDoc}
-     * <p/>
+     * <p>
      * Note that this set includes keys for any attributes tagged for removal.
+     * </p>
      */
     @Override
     public Set<String> keys();