Implement Grape::API.recognize_path

[namusyaka]

ref #1072
I've tried to implement Grape::DSL::InsideRoute#recognize_path.
It returns value conforming the format like [original pattern, expanded params].

This is a first step. I'd like to hear your opinions.
Thanks.

[dblock]

We didn't address mounting an endpoint in multiple places, but eventually we will. So maybe we don't want @router?

[namusyaka]

Yeah, right. Removed.

[dblock]

It's on the right track, but shouldn't recognize_path return an endpoint?

[namusyaka]

@dblock Now recognize_path returns an instance of Grape::Endpoint. How about this?

[dblock]

Very good. I think the last thing we need is a README entry that explains how you can use recognize_path from the outside of an API, so given a API < Grape::API, calling recognize_path to get a endpoint that would match.

[namusyaka]

I think the last thing we need is a README entry that explains how you can use recognize_path from the outside of an API, so given a API < Grape::API, calling recognize_path to get a endpoint that would match.

Hmm, makes sense. If I understand thing correctly, recognize_path should be implemented as a class method of Grape::API.
Maybe we can't call recognize_path outside of an API, without tricky code.
So I moved the method place from InsideRoute to API.
Could you please check this?

[dblock]

Perfect, merging.