* Spec output of Settings::Exports::BlockedAccountsController

* Spec output of Settings::Exports::FollowingAccountsController

* Spec output of Settings::Exports::MutedAccountsController

* Spec Settings::Exports::BaseController

This commit removes duplicate specs in classes inheriting
Settings::Exports::BaseController as well.

* Set delete_modal preference to true by default
* Does not show confirmation modal if delete_modal is false
* Add ja translation for preference setting page

In single user mode, visitors are redirected to the single user's
profile page.  So, if you are the owner without a session, you start
from that page, click the login button and authenticate yourself
expecting you'll soon get started with the home page, but in reality
you'll get redirected back to where you started from -- your own
profile page.

This fixes the behavior by redirecting you home after login if you
have started from your own profile page.

Resolve #3270

(You may think that we need account deletions, but this way would've just orphaned the db records)

- Increase coverage to exercise all parts of each action
- Move into namespace to share common code
- Misc refactor of each action for smaller methods, simpler code

* Cover StreamEntriesController more

* Remove redundant instructions in StreamEntriesController

@account is used by the view.

Introduce recent to Follow, as Account and other models have.
This change also adds specs for the scope and the dependents.

* Introduce recent scope to Status and StreamEntry

Introduce recent scope to Status and StreamEntry as Account has.

* Cover AccountsController more in AccountsController

* Add spec files for feed and media cleanup workers

* Add coverage for feed and media cleanup schedulers

* Clean up feed and media cleanup workers

This change also adds a specification for the method.

* Remove allowed_languages and add filtered_languages

* Use filtered_languages instead of allowed_languages