Sanitize improvements

[kimili]

I've been finding the Wikipedia::Page.sanitize function to be very useful. However, I've also been finding it a bit too heavy handed in what it decides to strip out and ignore. This update adds some parsing of simple Wikimedia template tags. Some of the additions include:

• Typographic tags Things like Em Dash, Spaced En Dash, Bullets, Middots and so on.
• Parsing of language specific tags. This finds tokens that define text in languages other than the main document language and converts it to HTML as a <span> with the appropriate lang attribute.
• Old Style Date parsing.
• Also, when the sanitized text is only a single paragraph, I've wrapped a <p>…</p> element around it for consistent formatting.

I've updated the sanitization test as needed and added another one which includes the old style date handling.

These changes are useful to me. I hope they can be useful to others, too.

[pietromenna]

Hi @kimili ,

Thank you very much for your contribution!