While the LDAP search is case insensitive, the array which is returned from
ldap_get_entries() will only use lowercase. This means that if one
configures the plugin to look for e.g. "givenName", no results
will be returned.
The plugin currently supports SSL (by using a ldaps:// URI as the
hostname of the LDAP server) and unencrypted LDAP. This patch
also adds StartTLS support, which is used by many LDAP servers.
