Render URL property values as clickable links

[zaqifathis]

Property values that are URLs (http/https/www) are now rendered as anchor tags opening in a new tab, instead of plain text. Applies to single and multi-value fields. Values are trimmed before matching so leading/trailing whitespace no longer prevents detection.

[hlg]

Do we really want to scan every single attribute value, including numerical and boolean values? This should only be applied to attributes of defined type IfcURIReference (even though checking the type might take more time. I would not match text without a scheme/protocol - hence with just www in the beginning. That is not specific enough and we would have to accept any other domain name as well.

Also, the table cell does not need to be passed to the function. Keep the function to enclosing the URL.

Thumbs up for escaping HTML.