rather than augment (tighten) parent groups.

Note that now a valid group is None, which makes a subobject public,
even a parent is protected.

  - object[entryname] can fail with attribute as well as type error
  - flatten didn't work with multiple values\
  - inserted base was not absolute

Added transaction support.

If authentication is performed, then the name of the authenticated
user is saved in the request with the name 'AUTHENTICATED_USER', and
will be passed to called objects through the argument name
'AUTHENTICATED_USER'.

Now the value must contain white space to be considered an error
message.

  - Butter realm management
  - Automatic type conversion
  - Improved documentation
  - ...

implemented.  The module needs to be retested after adding some new
features.

  - Provide a first cut authentication.authorization scheme
  - Fix several bugs
  - Provide better error messages
  - Provide automagic insertion of base
  - Support Fast CGI module publisher.