Add redirect 301

[fulldump]

If a url like /users/ is received, the final slash is removed automatically, and it matches with the following nodes chain:
<root> -> users
However, it should match with:
<root> -> users -> <empty string>
So, the typical CRUD in the examples should be these nodes:

<root>
    users
        <empty>  (handle GET, POST) `/users/`
        {user_id}  (handle GET, PATCH, DELETE) `/users/22`

Finally, if the url matches <root> -> users, (the url_parts array still contains an empty item) so in this case, return an automatic redirect to the same url with slash (better a relative url).

NOTE: this way needs an extra node for users