tree module:  * Documentation updates  * Change flatten_subtree() method to only flatten sub-tree under the    node name given exh module:  * Updated _flatten_ex_tree() method to reflect changed functionality of    tree.Tree.flatten_subtree() method
tree module:
 * Documentation updates
 * Change flatten_subtree() method to only flatten sub-tree under the
   node name given
exh module:
 * Updated _flatten_ex_tree() method to reflect changed functionality of
   tree.Tree.flatten_subtree() method

pmacosta/putil,pmacosta/putil