Add named routes

[alexisbz]

Context

As of today, Caesar has no such a thing as named routes.

Named routes could be useful, for example to add a util named MakeURL on the router struct for example.

For instance, with the following route :

func RegisterRoutes(
           // ...
) *caesar.Router {
         // ...
    router.
          Post("/auth/reset_password/{jwt}", forgotPwdController.Show).
          As("reset_password.show")

We could do something like :

router.MakeURL("reset_password.show", "<my_jwt>")

Acceptance criterias

• Add the As method, that adds a name to a route.
• Add a MakeURL method on the Router struct.