Add endpoints for pocket proxy

[k88hudson]

For implementing recommendations in mozilla/activity-stream#870, we need some endpoints to our test pocket endpoints. That includes:

• the /global-recs endpoint, which takes an optional count parameter (defaults to 3) and returns a status number and an array of suggested items
• the /item-recs endpoint, which takes a single URL and a count (number of items to return) and returns a list of suggested items related to that URL.

[pdehaan]

the /global-recs endpoint, which takes no query parametres and returns a status number and an array of suggested items

How many items should be in the array? Or should we pass a count to this endpoint as well?

[k88hudson]

Aha, you're right -- this does take a count, I think it is 3 by default