normalize /index.html behavior

Automatically adding the index.html to any route without checking if the
path has already an extension. Now, Acrylamid only appends an `index.html`
to a final URL if the location ends with a trailing slash.

The index pagination route has been changed to `/page/:num/`, notice the
trailing slash. If you use the default index pagination route, this will
immediately break as Acrylamid tries to create a file named `:num`.
sitemap excludes drafts with a different route than the permalink
normalize configuration as early as possible

fixes issues where code relies on a specific format before the
configuration has been normalized.