[COLLECTIONS-523] Add javadoc and close pull request. This closes #2.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/collections/trunk@1654521 13f79535-47bb-0310-9956-ffa450edef68

src/main/java/org/apache/commons/collections4/map/PassiveExpiringMap.java

@@ -425,6 +425,12 @@ public class PassiveExpiringMap<K, V>
         return System.currentTimeMillis();
     }
 
+    /**
+    * Add the given key-value pair to this map as well as recording the entry's expiration time based on
+    * the current time in milliseconds and this map's {@link #expiringPolicy}.
+    * <p>
+    * {@inheritDoc}
+    */
     @Override
     public V put(final K key, final V value) {
         // record expiration time of new entry