Add follow button to stdout

Switched to a more angular style for follow button and applying change set onto drone:master instead of drone:exp now.

The first two commits are fixes for problems I was having:
* extraneous `/` in URL for clicking the "rebuild" button causing 404s (looks like goji is strict about that?)
* update `stdout.js`'s endpoint from `/api/feed/stdout/:id` -> `/api/stream/stdout/:id`

The last commit is mine and now uses the angular method for binding handlers and scoping (I think). CSS is always debatable.

This is a followup to #488 (based off drone:exp) and issue #485.