initial draft

@mhoeber , this is an early take as I am waiting on replies from a couple of people, but I'd appreciate your sense of whether I've missed anything that's on the release page: https://edx-wiki.atlassian.net/wiki/display/ENG/Release+Page%3A+2014-06-24
add:  In the Download or view student data section, updated the example report to include the new User ID column.