Update Writer\Writer.php

Improve comparison regex-path.
See documentation for PHP REGEX flags : http://www.php.net/manual/en/reference.pcre.pattern.modifiers.php

Author: jbelien

src/Writer/Writer.php

@@ -103,7 +103,7 @@ protected static function getTextString(string $key, $value, int $indentSize = 0
                 return self::getText($key, $value, $indentSize, $indent);
             } elseif (preg_match('/^\{.+\}$/', $value) === 1) {
                 return self::getText($key, $value, $indentSize, $indent);
-            } elseif (preg_match('/^\/.+\/[a-z]*$/', $value) === 1) {
+            } elseif (preg_match('/^\/.+\/[imsxeADSUXJu]*$/', $value) === 1) {
                 return self::getText($key, $value, $indentSize, $indent);
             } else {
                 return self::getText($key, '"'.$value.'"', $indentSize, $indent);