TODO

0. implement __dir__
2. Add dummy text backend to telnet_auth.
3. clean-up logging in standalone shell.
5. write documentation (sphinx)
6. correct exceptions.
7. Take $TERM from the client terminal. (In case of a fuse-filesystem-system, we can easily have another $TERM for each connection.)
8. test 'hosts' vs. 'host'
10. test exceptions in action.
12. we should have at least a role named 'host' in SimpleNode
17. When moving to another thread,  hostcontext should be aware of that. Guarantee thread safety.
18. Implement walk-function
20. implement filesystem in userspace mapping.   (sftp, etc...)
21. update README
22. Rename get and put to get_file and put_file and wrap it around Host.open()
24. Inspection of required_property gives NotImplementedError, show a nicer message.

25. Allow creation of Env() objects which disallow connection to hosts. By
    using this, it's possible to safely and quickly evaluate all Query objects.
    And Look for reverse relationsships. e.g.  List all the queries that point
    to a certain node. "--list-references" command.
26. Fix select_node parameters and test it. (filter should be an inspection
    filter instance.)

27. Disallow overriding of 'host', 'hosts' and others in Service.


28. Better document IsolationIdentifierType
29. Show item_mapping of current node in --inspect
30. Create command to enable/disable interactive property of the Console

https://code.google.com/p/fusepy/source/browse/trunk/sftp.py