Fixed: Issue #3819 v3.1 Unescaped strings in language files after installation vs source throws 500 error

Author: Till Brehm

interface/lib/classes/tform_tpl_generator.inc.php

@@ -311,6 +311,8 @@ function lng_add($lang, $formDef) {
 			$fp = fopen($lng_file, "w");
 			fwrite($fp, "<?php\n");
 			foreach($wb_out as $key => $val) {
+				$val = str_replace("'", "\\'",$val);
+				$key = str_replace("'", "\\'",$key);
 				$new_line = '$wb["'.$key.'"] = '."'$val';\n";
 				fwrite($fp, $new_line);