Authenticate a user against an LDAP directory
Useful for Windows Active Directory and other LDAP-based organisations
to maintain a single password across the organisation.
Optionally authenticates only if a member of a given group in the directory.

By default, the person must have registered with Friendica using the normal registration 
procedures in order to have a Friendica user record, contact, and profile.
However, it's possible with an option to automate the creation of a Friendica basic account.

Note when using with Windows Active Directory: you may need to set TLS_CACERT in your site
ldap.conf file to the signing cert for your LDAP server. 

The configuration options for this module may be set in the .htconfig.php file
e.g.:

// ldap hostname server - required
$a->config['ldapauth']['ldap_server'] = 'host.example.com';
// dn to search users - required
$a->config['ldapauth']['ldap_searchdn'] = 'ou=users,dc=example,dc=com';
// attribute to find username - required
$a->config['ldapauth']['ldap_userattr'] = 'uid';

// admin dn - optional - only if ldap server dont have anonymous access
$a->config['ldapauth']['ldap_binddn'] = 'cn=admin,dc=example,dc=com';
// admin password - optional - only if ldap server dont have anonymous access
$a->config['ldapauth']['ldap_bindpw'] = 'password';

// for create Friendica account if user exist in ldap
//     required an email and a simple (beautiful) nickname on user ldap object
//   active account creation - optional - default none
$a->config['ldapauth']['ldap_autocreateaccount'] = 'true';
//   attribute to get email - optional - default : 'mail'
$a->config['ldapauth']['ldap_autocreateaccount_emailattribute'] = 'mail';
//   attribute to get nickname - optional - default : 'givenName'
$a->config['ldapauth']['ldap_autocreateaccount_nameattribute'] = 'givenName';

...etc.
