This object describes the success or the failure of an attempt
to authenticate a user.
The boolean flag valid specifies a success (valid) or a failure
(not valid).
The document result contains in the case of a success the
authentication xml that is store in the session.
In the case of a failure, the result can contain information
about the failure (or the document can be null).
If in the case of a failure the result contains information,
the xml must follow this format:
if data is available data is included, otherwise:
No information
If exception message contains info, it is included into failed
The root element is removed and the contained elements are stored
into the temporary context.