Route.methods nesting artifact

[ahopkins]

The Route.methods property is generally nested as follows:

{
    "/some/path": set("GET", "POST")
}

However, this level of nesting is not only a breaking change, it is not necessary. It is the result of an earlier iteration of the router that was since abandoned. It seems this artifact has remained, and is no longer necessary.

---

Can be solved:

    def _finalize_methods(self):
        self.methods = set()
        for handlers in self.handlers.values():
            self.methods.update(set(key.upper() for key in handlers.keys()))

[ahopkins]

In actuality, I believe the root cause of this is that Route.handlers no longer needs to be nested:

Change:

self.handlers = defaultdict(lambda: defaultdict(list))

To:

self.handlers = defaultdict(list)

However, much more edge case testing would need to be done before making that change.

[ahopkins]

#7 fixes the method issue, but leaving this open for further investigation regarding the handler nesting.