LangRouter/Babel compatibility

[zaigham]

Currently Redirector doesn't really work with LangRouter, and possibly Babel/MultiContext installations.

eg, ru/old-url -> ru/new-url doesnt work.

Although it saves the information correctly when saving the document. But when it gives back the "target", it is without the "cultureKey" eg. site.com/new-url hence it fails.

Ref:
Jako/LangRouter#5

Redirector/core/components/redirector/elements/plugins/redirector.plugin.php

Lines 59 to 60 in b2c5ac1

	$target = $redirect->get('target');
	$modx->parser->processElementTags('', $target, true, true);