More status specs (#2564)

More status specs (#2564)

* Add rough outline of coverage needed for public timeline

* Specs for visibility, replies, boosts

* Specs for silenced account

* Specs for local_only option

* Specs for blocks and mutes

* Add tentative spec around including other silenced account statuses

* Add with_public_visibility scope

* Add simple coverage for tag_timeline

* Tag timeline includes replies

* Replace tag.statuses with a tagged_with scope in tag timeline method

* Use with_public_visibility in tag timeline

* Extract common scope between public and tag timelines to method

* Extract local domain check to local_only scope

* Extract local_only check to starting scope method

* Move list of excluded from timeline account ids to account model

* Simplify excluded accounts list on account model

* Only join accounts when needed

* Rename method for account specific filtering

* Extract method for account exclusions

* Fix bug where silenced accounts were not including statuses from other silenced accounts

* DRY up filter application from account or no account

* timeline_scope can be private

* Add spec showing that account can find its excluded accounts ids

* Add spec which fails if local_only does not have a left outer join

* rubocop