The goal of this ticket is to implement a client which sends a lightweight API request to power the native article view w/o having to make the full mobileview request.
== Acceptance Criteria
- [ ] "Fetcher" API accepts a title, returns a promise which resolves to a model object for article "preview" (name not final)
- [ ] "Preview" object contains: description, lead image (i.e. "thumb" at lead image resolution), first section HTML, and TOC
- [ ] Business logic for using cached mobileview response and falling back to preview API request is implemented
== Business Logic
Given I am on the native article view
When the mobileview response is cached
Then the mobileview response data is displayed in the native article view
Given I am on the native article view
When the mobileview response is not cached
Then I will get data for the native article view using a lightweight MW API query