Allow slash ended path info

Why this PR ?
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Modern browser often auto-complete your URIs, and adds a slash at the end. ( Did you never go to ```/admin/``` because of Firefox ? )

Inspired by Github's way to "fix" it, here's a solution: ignore the last slash of the path info.
Here's an example:
Try to go to https://github.com/thelia/thelia and https://github.com/thelia/thelia/

The result is the same.

So why won't we allow to do that in thelia too ? :-)
where did you define the slash_ended_uri variable ?