Shorturl fails when user is logged in
[Shorturl service](https://github.com/camptocamp/c2cgeoportal/blob/master/c2cgeoportal/views/shortener.py#L108) complains 
`AttributeError: 'O' object has no attribute 'email'`

The email user attribute is actually named `mail` ! This is a problem in C2C

diff --git a/geoportailv3/views/authentication.py b/geoportailv3/views/authentication.py
index 250f24d0..7c724318 100644
--- a/geoportailv3/views/authentication.py
+++ b/geoportailv3/views/authentication.py
@@ -33,6 +33,7 @@ def get_user_from_request(request):
         user = O()
         user.id = 0
         user.username = username
+        user.email = None
         connector = get_ldap_connector(request)
         cm = connector.manager
 
['geoportailv3/views/authentication.py']