Rename user.authtoken to user.password; drop obsolete team.authtoken.

Stop overloading the password field with multiple tokens, because
this hinders us when presenting an appropriate UI for the field.
IP address is already stored in the ip_address field.

Changes behaviour for LDAP, which will now just match user.username,
which shouldn't be problematic. Drops unused column team.authtoken.
Display team.login as "ID" to avoid confusion with user.login.
No more highlighting.php
Improve user management by allowing to set password and adding links.

User passwords may now be (re)set from the user edit page, not on
a separate genpasswds page. The latter is now reserved to only
setting bulk passwords; which is now limited to only those users
with a team role, as we probably do not want to do bulk password
setting for admins or judgehosts.