Add log message for API procedure createLdapUser()

app/Api/User.php

@@ -66,8 +66,24 @@ class User extends \Kanboard\Core\Base
         return $valid ? $this->user->create($values) : false;
     }
 
+    /**
+     * Create LDAP user in the database
+     *
+     * Only "anonymous" and "proxy" LDAP authentication are supported by this method
+     *
+     * User information will be fetched from the LDAP server
+     *
+     * @access public
+     * @param  string $username
+     * @return bool|int
+     */
     public function createLdapUser($username)
     {
+        if (LDAP_BIND_TYPE === 'user') {
+            $this->logger->error('LDAP authentication "user" is not supported by this API call');
+            return false;
+        }
+
         try {
 
             $ldap = LdapClient::connect();