fix to validate URLs with date/numeric ranges

[mxsnq]

Provided pattern only checks for valid URLs, so I made a simple fix to remove date and range specs before applying it. Possible improvements:

• use more human friendly URL validator
• disallow date/range patterns in some parts of URL (e.g. scheme)

[mxsnq]

Rewrote this with try { new URL ... }, it matches date/numeric ranges in path