Ship cookie parsing as a computed value

[aturon]

As a follow up to #80, the cookie example should be polished up and moved into Tide proper, so that applications can use it.

[jimmycuadra]

Is there a place that gives an explanation of "computed value?" I've seen this term used a few times in the Tide blog posts but I don't get what it means.

[jimmycuadra]

Nevermind, I found the answer in the API docs:

struct tide::Computed

An extractor for computed values.

Endpoints can use this extractor to automatically compute values for a request, and re-use cached results if those values have been computed previously (e.g. in some middleware).