Post edit task recommendation based on current page

Create getSuggestions method which handles the heavy lifting
of the generator allows us to not break existing getpages task type.

Gated  behind $wgGettingStartedRunTest and only runs
when user is logged in.

1) Disable post edit notification

... and when the postEdit hook fires ...

2) Request 1 suggested article
3) Parse the response
4) Render and show the notification

Change-Id: I9bd86d6207455c2cb27164bdf18323b01b77f494
Merge "Post edit task recommendation based on current page"