s/rails/rake/

If the file package is not installed, we get "Validation failed: File has contents that are not what they are reported to be" when upload media.

Missing -u parameter to specify the mastodon user.

must be added to the Sidekiq invokation in your systemd file

The pull queue will handle link crawling, thread resolving, and OStatus
processing. Such tasks are more likely to hang for a longer time (due to
network requests) so it is more sensible to not make the "in-house" tasks
wait for them.

Closes GH-745.

make status pagination headers generation more lax about next page
existing

Heroku uses the referrer URL to point at the repo that should be deployed; from this page that includes part of a path that breaks the deployment (specifically /blob/master/docs/Running-Mastodon/Heroku-guide.md).

I've replaced the vanilla address with one that includes a specific reference to the root of the repo

work flawlessly was a nightmare). WARNING: This commit makes the web UI connect to the streaming API instead
of ActionCable like before. This means that if you are upgrading, you should set that up beforehand.