Draft of release notes for 10-7

@lamagnifica @mhoeber @explorerleslie Please review. (Leslie - in particular, can you review the bullets that have to do with discussions?) Built version at http://draft-107-release-notes.readthedocs.org/en/latest/10-07-2014.html.
some of the setup is done in Studio. Probably not worth pointing it out though as it's so awful