Release notes 12-16-14

@srpearce @fredsmith  @explorerleslie 

need to complete by 11:00

FYI @lamagnifica @catong 
Alison pointed out last week that this announcement is a bit ambiguous (I didn't have time to get the change in). Suggest something like this:

Students who enroll in a verified course must currently complete the ID verification process before completing the payment process. Soon, students will be able to complete the payment process without completing the verification process, and vice versa.