Automatic Personal Blogs
All users should have a blog by default and automatically subscribe to the default blog of their contacts. The blogs of the contacts should show up in the combined feed (#417 (closed)). Writing a new post into the default blog should be quick and easy.
As for other blogs, the group descriptor is a BDF list with three elements: name (string), author_name (string) and the author's long-term public_key (raw). The name should be a deterministic identifier that is either known beforehand or can be calculated from the given information. I would suggest to not use "$author_name's blog" as the internal name to allow for localization. The name could be something like "org.briaproject.BLOG_NAME" which will be shown as "$Author's blog" in an English UI.
This is a sub-ticket of #134 (closed).