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* Without this patch, when the user tries to disconnect from CubicWeb instance,
  the SAML process is going to use the get_saml_uri_from_request method from
  SAMLLogMixin class instead of SAMLLogout
* It redirects to a new dedicated SAML connection URI causing a new connection
  to CubicWeb instead of redirecting to the SAML Identity Provider server

* With these views, the user is automatically redirect to SAML IdP server
  with the login and loggout actions

* For each utils methods like get_user, the client identity is check to
  ensure the receiving data come from the SAML server