Strip html tags & remove non printable characters

Html characters are not permitted by skroutz according to the specifications
Also non printable characters are breaking xml, even when enclosed in CDATA.

Here is a pastebin which removes html & non printable characters.

You can apply the function formatField in pastebin before creating a CDATA section in simplexml.php. Example simplexml.php here
PS: I could fork and PR you back, but I didnt find any git repo.