Begin using Traceur for arrow functions
Update docs
Tidy up
Re-order feed tests
Add more tests for feed endpoints
Complete feed endpoint tests
Test duplicate feeds
Use child injectors
Correct injector order
Send correct errors
Simplify error lookup
Use logger
Use VError for support scripts
Fix username validation
Correctly append links to all entities
Update docs
Tidy up
Remove user-follow-status example
Remove feedSubscribe

Simplifying model until infrastructure is solidified.
Feed spec improvements

* Improve test descriptions
* Improve detection of promise rejections
* Use services for test setup instead of API – only use the API when
  we are testing something.