Commit 17f9b7f070dbe17b2844a8b4dd428 in the pgweb repository removed
the /static/ portion on all doc URLs, leaving a redirect in place. To
avoid incurring a needless redirect, remove the /static/ part in the
links to the PostgreSQL documentation.

The /static/ URLs stem from a time when there were interactive docs
that had comment functionality. These docs were removed a very long
time ago, but the static differentiator was left in place until now.

Reviewed-by: Mel Kiyama