Enhance 404 error responses for non existing routes

[g0di]

For the moment, when requesting an unexisting route of an API using the library, we get a 404 error with a detail message just stating that the requested route does not exist.

We may enhance this response to include as well:

• In the detail property, mention which route has been requested
• In the detail property provide a suggestion about what other existing route the client might wanted to actually request. This is useful for catching typos
• In the object add custom property containing the requested route
• Eventually, add a property listing all routes more or less close to the requested URI