Updates for language auto detect, fixes for PHP 7.4

There was a bug in ther SQL interface class where the folder was just
called "Interface" which is not an allowed Namespace name. Renamed to
SqlInterface

Moved the detect lang/etc function used in Form/Generate,
Template/SmartyExtend and Admin/Backend to Language/GetSettings.

Fixed some test class calls

www/lib/CoreLibs/DB/IO.php

@@ -382,7 +382,7 @@ class IO
 	public function __construct(
 		array $db_config,
 		?\CoreLibs\Debug\Logging $log = null,
-		?bool $db_debug_override = null,
+		?bool $db_debug_override = null
 	) {
 		// attach logger
 		$this->log = $log ?? new \CoreLibs\Debug\Logging();