Make it easier to distinguish user with the same name in the share drop down

Make it easier to distinguish user with the same name in the share drop down: If you have many users called "John Doe" and you type "John" in the share dialog you see a lot of users with the same user name. On hover we show the username but this is also often not really useful. Especially if the UID is a cryptic LDAP UUID for example. I think it would make more sense to show more user friendly information, for example the email address would be a useful information to distinguish the users in many situations.