Ahodges/doc/relnotes20140826

@srpearce , @explorerleslie , @jzoldak please review and tag others to do so as appropriate.
Can we leave out "user experience" and "user interface"? These words are a bit techy and can be confusing, and I don't think they're necessary: 

A new design for course discussions is coming! New controls will provide consistent ways to take action on _(sp: or "to interact with")_ posts. Additionally, a set of colorful badges will make identifying posts easier.