Add downstream build notification HipChat icons
Limit build time output to 2 decimal places

Unlikely that this extra precision provides value to anybody ever.
Add completed build notification HipChat emoticons
Add "not building" build notification HipChat emoticons
Add (branch) HipChat emoticon for non-master builds
Handle non-pass/fail statuses consistently

No point special-casing the others, just use "else".
Merge pull request #43 from 99designs/hipchat-icons

Add HipChat icons to build notifications