Upgrade function since($stamp) to consider weeks, months, years #2008

Is your feature request related to a problem?

Inside textpattern/lib/txplib_misc.php is the function since($stamp) which seems to present the since-format for certain timestamps. It doesn't seem to consider cases where several weeks, months or even years have passed.

What is the feature?

Include weeks, months and years in the function. Simple examples:

• If timestamp is older than 7 days, show "1 week"
• If timestamp is older than 31 days, show "1 month"
• If timestamp is older than 366 days, show "1 year"