The server script should try to rstrip '/' when serving pages.

The server script currently has capability to try to serve pages without a .html
suffix, to support mapping:

site.com/2013/06/some-slug --> site.com/2013/06/some-slug.html

However, some internal links in websites add a trailing slash after the slug,
even though it's a HTML file and not a directory:

site.com/2013/06/some-slug/ --> site.com/2013/06/some-slug.html

Augments the solution for #1038