* Redirect to default URL after 1FA when default policy is one_factor.
User is now redirected to the default redirection URL after 1FA if
the default policy is set to one_factor and there is no target URL
or if the target URL is unsafe.
Also, if the default policy is set to one_factor and the user is already
authenticated, if she visits the login portal, the 'already authenticated'
view is displayed with a logout button.
This fixes#581.
* Update users.yml
* Fix permissions issue causing suite test failure
Providing a GA tracking ID allows administrators to analyze
how the portal is used by their users in large environments,
i.e., with many users.
This will make even more sense when we have users and admins
management interfaces.
A message is now displayed to the user when he first sign in
in Authelia letting him know that a device must be enrolled.
Also introduce a message letting him know when he is already
authenticated.