resolving the confusion from self-chain replies ultimately linking to a
non-self status. Adjust filters

Fix wrong person being notified after nested reblog call, fix favourites leaking private toots in Atom feeds

Better initial state for unlisted/nsfw toggles

coming in via Salmon.

Currently no way to prevent remote follows, but they will only receive public
and unlisted posts

Reflect "requested" relationship in API and UI
Reflect inability of private posts to be reblogged in the UI
Disable Webfinger for locked accounts

Filters out hidden stream entries from Atom feed
Blocks now generate hidden stream entries, can be used to federate blocks
Private statuses cannot be reblogged (generates generic 422 error for now)
POST /api/v1/statuses now takes visibility=(public|unlisted|private) param instead of unlisted boolean
Statuses JSON now contains visibility=(public|unlisted|private) field