Speed up fetching of posts in PleromaFE

Currently, it seems to wait for some unrelated endpoints to return first. Might even be possible to do it right at the start without waiting for the config.json to return.

I've observed this too. When you load a user profile, for example, the first call to /api/v1/accounts/:id/statuses is to fetch the pinned posts, and once that completes it seems to fire off a GET to /api/v1/accounts/:id/statuses for the profile timeline and the media_only timeline.

If we could reduce the user profile timeline to a single API call (one RTT to the database) that would be ideal. Perhaps we could get the BE to ignore pinned=true if max_id is set as well? This just means the FE could request 20 statuses and receive 20 + pinned, but that shouldn't be a deal breaker.

Additionally it seems like the notifications panel timeline isn't fetched concurrently either.