Integrate Yaga in APIv2

[bleistivt]

It would be nice to have namespaced APIv2 controllers for all frontend actions:

• [ ] GET "best" content of all flavours
  • [ ] GET yaga-best/all
  • [ ] GET yaga-best/recent
  • [ ] GET yaga-best/reactions/{id}
  • [ ] GET yaga-best-users/{id}/reactions/{reactionID}
  • [ ] GET yaga-best-users/{id}/best
  • [ ] GET yaga-best-users/{id}/totals
• [ ] GET available actions/totals
  • [ ] GET users/{id} {yaga-reactions: [...]}
  • [ ] GET comments {yaga-actions: [...]}
  • [ ] GET discussions {yaga-actions: [...]}
• [ ] GET reactions for content (extend comment/discussion API)
  • [ ] GET comments {yaga-reactions: [...]}
  • [ ] GET discussions {yaga-reactions: [...]}
  • [ ] GET yaga-reactions/activity/{id}
  • [ ] GET yaga-reactions/comment/{id}
  • [ ] GET yaga-reactions/discussion/{id}
  • [ ] GET yaga-reactions/{type}/{id}
• [ ] PUT, DELETE a reaction (reacting to content)
  • [ ] PUT yaga-reactions/{type}/{id}/{actionID}
  • [ ] DELETE yaga-reactions/{type}/{id}/{actionID}
• [ ] GET a users badges
  • [ ] GET users/{id} {yaga-badges: [...]}
  • [ ] GET yaga-badges/users/{id}
• [ ] GET all recent awards of a badge
  • [ ] GET yaga-badges/{id}
• [ ] PUT, DELETE a badge award (un-/awarding a badge)
  • [ ] PUT yaga-badges/users/{id}/{badgeID}
  • [ ] DELETE yaga-badges/users/{id}/{badgeID}
• [ ] GET leaderboard
  • [ ] GET yaga-leaderboard/{timeslot}
• [ ] GET a users rank (extend profile/me API)
  • [ ] GET profile/me {yaga-ranks: [...]}
  • [ ] GET yaga-ranks/users/{id}
• [ ] PUT, DELETE a users rank
  • [ ] PUT yaga-ranks/users/{id}/{rankID}
  • [ ] DELETE yaga-ranks/users/{id}/{rankID}

The old controller methods should be stripped of their functionality and call the new API.