initial working version of ptree, walk_nodes is a bit slow
improved 2-pass method, can now get node/branch size as % of total. I have some doubts about whether this will work properly for all types of unbalanced tree, though...
I think it will now correctly visit each node only once, without having to store the number of visits in a separate dict
sorting nodes by name, size, natural order
Merge branch 'tmp' into pttree
print details of arrays/tables if they fall at exactly max depth
catch NotImplementedError raised on <VLArray>.size_on_disk and warn instead
fixed a bug where natural order sorting of nodes would fail when where=='/' (root is not in root._v_children)
Merge branch 'develop' of github.com:PyTables/PyTables into pttree
improved handling of hardlinked nodes (don't count them multiple times when computing branch size)
Merge pull request #400 from alimuldal/pttree

pttree - a script for printing PyTables HDF5 file contents as a pretty ASCII tree