fix(tracklist): correct focus of tracks
chore(client): cleanup dependencies
feat(client/socket): add multiple improvements

- add debug flag for socket
- add ability to wait for only one message using socket#once
- add ability to unregister event registrations via socket#off
- give socket own angular module
fix(css): minor changes in markup
test(integration): add simple backend specification test

- add test infrastructure
- add simple backend compatibility spec
  - runs via `karma start src/test/javascript/config/karma.backend.js`

Closes #14
docs(README): add client and server side readmes
Merge branch 'master' of github.com:Nikku/silent-disco