Template:VSAFE metrics dashboard/doc

Usage

 * articles = number of articles in scope for report
 * domains = number of unique domain names captured in report
 * percent_reliable = percentage of URLs that are to known reliable sources
 * percent_flagged = percentage of URLs that are to flagged (poor reliability) sources
 * percent_unrated = percentage of URLs to sources not rated for reliability
 * last_updated = timestamp of last report update