* Wrap methods of ProcessFeedService::ProcessEntry in classes

This is a change same with 425acecfdb15093a265b191120fb2d4e4c4135c4, except
that it has the following changes:

* Revert irrelevant change in find_or_create_conversation
* Fix error handling for RemoteActivity

* Introduce Ostatus name space

* Add dependency on idn-ruby to speed up URI normalization

* Use normalized_host instead of normalize.host when applicable

When we are only interested in the normalized host, calling normalized_host
avoids normalizing the other components of the URI as well as creating a
new object

* Fix #2672 - Connect signed PuSH subscription requests to instance domain

Resolves #2739

* Fix return of locate_subscription

* Fix tests

* Add Request class with HTTP signature generator

Spec: https://tools.ietf.org/html/draft-cavage-http-signatures-06

* Add HTTP signature verification concern

* Add test for SignatureVerification concern

* Add basic test for Request class

* Make PuSH subscribe/unsubscribe requests use new Request class

Accidentally fix lease_seconds not being set and sent properly, and
change the new minimum subscription duration to 1 day

* Make all PuSH workers use new Request class

* Make Salmon sender use new Request class

* Make FetchLinkService use new Request class

* Make FetchAtomService use the new Request class

* Make Remotable use the new Request class

* Make ResolveRemoteAccountService use the new Request class

* Add more tests

* Allow +-30 seconds window for signed request to remain valid

* Disable time window validation for signed requests, restore 7 days
as PuSH subscription duration (which was previous default due to a bug)

Since there is little point in retrying so often when a service is down
or does not exist anymore. Subscriptions are renewed 1 day before they
should expire, so retrying in 30 minutes, then 2 hours, then 12 hours
is fine. If even after that, the remote server does not work, there is
little sense in retrying more often than once a day

Also, uniqueness of the job should ensure that failed retries will
not result in multiple retries for the same endpoint when the next
resubscription cycle comes

* Introduce domains method to Account relation

Account had followers_domains method, which was excessively specific.
Let relation of Account have domains method instead.

* Move follow_mapping in Account to AccountInteractions

* Introduce shared examples for AccountAvatar inclusion

* Cover Account more

* Make Pubsubhubbub::DistributionWorker handle both single stream entry
arguments, as well as arrays of stream entries

* Add BatchedRemoveStatusService, make SuspendAccountService use it

* Improve method names

* Add test

* Add more tests

* Use PuSH payloads of 100 to have a clear mapping of
1000 input statuses -> 10 PuSH payloads

It was nice while it lasted

* Do not cancel PuSH subscriptions after encountering "permanent" error response

After talking with MMN about it, turns out some servers/php setups do
return 4xx errors while rebooting, so this anti-feature that was meant
to take load off of the hub is doing more harm than good in terms of
breaking subscriptions

* Update delivery_worker.rb

* Framework for delivery worker spec

* Refactor of pubsub delivery worker

* Add specs for valid challenge response from pubsub confirmation worker

* Refactor the pubsub confirmation worker

to all subscribers. IDN-normalize callback URLs for subscriptions on insert.

* add content-type in pubsubhubhub request header

* fix type

* Fix Scheduler::SubscriptionsScheduler, add worker test for it

* Change production log level of Sidekiq to "warn" instead of "info"

* Fix #2473 - Use sidekiq scheduler to refresh PuSH subscriptions instead of cron

Fix an issue where / in domain would raise exception in TagManager#normalize_domain

PuSH subscriptions refresh done in a round-robin way to avoid hammering a single
server's hub in sequence. Correct handling of failures/retries through Sidekiq (see
also #2613). Optimize Account#with_followers scope. Also, since subscriptions
are now delegated to Sidekiq jobs, an uncaught exception will not stop the entire
refreshing operation halfway through

Fix #2702 - Correct user agent header on outgoing http requests

* Add test for SubscribeService

* Extract #expiring_accounts into method

* Make mastodon:push:refresh no-op

* Queues are now defined in sidekiq.yml

* Queues are now in sidekiq.yml

* Fix #2119 - Whenever about to send a HTTP request, normalize the URI

* Add test for IDN request in FetchLinkCardService

* Perform IDN normalization on domains before they are stored in the DB

* Make private toots get PuSHed to subscription URLs that belong to domains where you have approved followers

* Authorized followers controller, stub for bulk action

* Soft block in the background

* Add simple test for new controller

* Rename Settings::FollowersController to Settings::FollowerDomainsController, paginate results,
rename "private" post setting to "followers-only", fix pagination style, improve post privacy
preferences style, improve warning style

* Extract compose form warnings into own container, show warning when posting to followers-only with unlocked account

* Remove trailing whitespace

* Use query methods instead of explicit .blank? checks

* Rewrite Atom generation from stream entries to use Ox instead of Nokogiri::Builder

StreamEntry is now limited to only statuses, which allows some optimization. Removed
extra queries on AccountsController#show. AtomSerializer instead of AtomBuilderHelper
used in AccountsController#show, StreamEntriesController#show, StreamEntryRenderer
and PubSubHubbub::DistributionWorker

PubSubHubbub::DistributionWorker moves n+1 DomainBlock query to PubSubHubbub::DeliveryWorker
instead.

All Salmon slaps that aren't based on StreamEntry still use AtomBuilderHelper and Nokogiri

* All Salmon slaps now use Ox instead of Nokogiri. No touch from status on account

Allow PuSH to distribute private toots with that condition

can be processed separately