improves on 4.1s fix for an XSS vulnerability exploitable on Internet Explorer. It also contains a number of important bugfixes, including
> the removal of improper logic that could result in infinite loops and
> fixed parsing for single-attributes with entities with DirectLex.
- can be used via html class like:
$clean_html = html::purify($html);
- using it now in eTemplate to remove malicious code from html:
a) when displaying "formatted text"
b) when "formatted text" get's input by the user
