* Consolidate webfinger string creation under Account#to_webfinger_s

* Introduce Account#local_username_and_domain for consolidation

* Clean up SQL output in Tag and Account search methods

* Add basic coverage for Tag.search_for

* Add coverage for Account.search_for

* Add coverage for Account.advanced_search_for

Checking reblog vs original status was happening in multiple places
across the app. For views, this logic was encapsulated in a helper
method named `proper_status` but in the other layers of the app, the
logic was duplicated.

Because the logic is used at all layers of the app, we extracted it into
a `Status#proper` method on the model and changed all uses of the logic
to use this method. There is now a single source of truth for this
condition.

We added test coverage to untested methods that got refactored.

Fix anchor tags in some wikipedia URLs being matches as a hashtag

as well as formatting of content

and atom feed generation to some extent, as well as the way mentions are
stored