Sylvia/docs/relnotes 7 30

@lamagnifica @mhoeber Please review. There's some back-and-forth about the PR with the Analytics changes in the Release HipChat room; I'll keep watching it and remove this info if necessary.
Does this work? In Studio, new publishing capabilities will make it easier for course authors to edit and publish content. We've simplified the publishing workflow and added clear indications so you'll know at a glance whether your content is published and released--and whether students can see it.