[#7406] add option to disable user registration
[#7406] add autoregister method for LDAP logins
[#7406] force user.display_name usage to go through prefs manager
[#7406] remove unused by_display_name lookups
[#7406] factor out some ldap helper functions
[#7406] LdapUserPreferencesProvider, for display_name
[#7406] add timing for ldap methods
[#7406] add caching to FieldPropertyDisplayName to help non-local pref cases
[#7406] documentation for LDAP config