* Begin coverage for account search service

* Coverage for hashtag query

* Coverage for calling local vs remote find based on domain presence

* Spec to check that exact matches are not duped

* Coverage of resolve option

* Coverage for account being provided

* Start to refactor account search service

* Isolate query username and domain methods

* Isolate exact_match method

* Extract methods for local and remote results

* Simplify local vs remote and account isoliation

* Extract methods for local and remote results

* Simplify de-dupe of exact match

* Simplify logic to check for non exact remotes

* Cache some methods

* Remove nil from exact_match from results array

* Return exact matches first

* Use find_remote even with no domain

Account.find_local is just an alias for Account.find_remote(user, nil) - so we
can not bother with the conditional here, and call find_remote directly.

* Fix #1141, fix #1126 - Work through UpdateRemoteProfileService for both <feed> and <entry> top-level tags

* Improve code quality, remove line unrelated to fix

These are currently user facing errors, but are not localized. This adds the
ability for these messages to be localized.

This implements all pending specs, and adds additional coverage for the
following functionality:

* Normal status creation
* Creating a reply status
* Creating a sensitive status
* Creating a status with spoiler text
* A status with no spoiler text gets an empty string for spoiler text
* Creating a status with custom visibility
* Creating a status for an application
* Processing mentions
* Processing Hashtags
* Pinging PuSH hubs
* Crawling links
* Attaching media

There are currently not specs for the two media validations that are performed
by `PostStatusService`. This adds specs for the validations that ensure that you
cannot attach more than four files, and that a status cannot have both image and
video attachments.

StreamEntry model. Simply render Salmon slaps as they are needed

redis-backed "mentions" timeline as redundant (given notifications)

removing web app capability from non-webapp pages

Fetching atom extracted from FetchRemoteAccountService and FetchRemoteStatusService
into FetchAtomService. Mentions of the constant "http://activityschema.org/collection/public"
skipped as it's not a real URL/user.