Migrate BlogController and FeedController to ViewModel
This uses two different view model instances for blog and feed.
- create test data with blog posts
- enter main blog feed and individual blogs, rotate screen
- add contact that writes blog posts and reblogs existing posts
- check that new posts produce notifications when not in blogs (or in other people's blogs)
- check posts get added to blog list if open when post arrives
- write/reblog blog posts yourself, check that it gets added to main blog feed