Added missing callbacks to AVMNodeService. This makes things slow.

Have to do something about that.
Added getPaths call to AVMService.  Retrieves all possible paths to a node.
Need to do timing tests.
I believe, the 6th version of a Pair template class. This one's public and 
perhaps when we have time we could use it in place of all the inner class
implementations.


git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/BRANCHES/WCM-DEV2/root@3964 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/avm/ChildEntryDAO.java

@@ -54,6 +54,13 @@ public interface ChildEntryDAO
      */
     public ChildEntry getByParentChild(DirectoryNode parent, AVMNode child);
     
+    /**
+     * Get all the ChildEntries corresponding to the given child.
+     * @param child The child for which to look up entries.
+     * @return The matching entries.
+     */
+    public List<ChildEntry> getByChild(AVMNode child);
+    
     /**
      * Update a dirty ChildEntry.
      * @param child The dirty entry.