* Remove redundant status.reply? in AtomSerializer#object

* Cover AtomSerializer more

* Remove trailing whitespace in i18n mailers

* Use query methods instead of #present? on AR attributes

* Delegate Status#account_domain method

* Delegate Mention #account_username and #account_acct methods

* selectively Revert "Fix regressions from #2683 (#2970)"

This reverts commit 72698bc3b4.

* Revert "Handle hashtags in spoiler_texts (partial fix for #699) (#2683)"

This reverts commit e2491680e6.

* Add <ostatus:conversation /> tag to Atom input/output

Only uses ref attribute (not href) because href would be
the alternate link that's always included also.

Creates new conversation for every non-reply status. Carries
over conversation for every reply. Keeps remote URIs verbatim,
generates local URIs on the fly like the rest of them.

* Fix conversation migration

* More spec coverage for status before_create

* Prevent n+1 query when generating Atom with the new conversations

* Improve code style

* Remove redundant local variable

so that when a reblog parse fails on another instance, it doesn't
look like a misattributed/stolen text

Receiving instances will then use their own missing image

Also, add <content /> to deleted statuses, since there was a reported
problem with the deletes and GNU social

* Fix regressions from #2683

Properly format spoiler text HTML, while keeping old logic for blankness intact
Process hashtags and mentions in spoiler text
Format spoiler text for Atom
Change "show more" toggle into a button instead of anchor
Fix style regression on dropdowns for detailed statuses

* Fix lint issue

* Convert spoiler text to plaintext in desktop notifications

* Fix #1057 (close #1819) - Move HTML-formatted bio from <poco:note /> to <summary type="html" />

* Ensure <poco:note /> is plaintext for remote accounts, also, by stripping out HTML

Also improve efficiency of the mastodon:maintenance:add_static_avatars task

* Fix #1870 - Strip control characters out of strings in AtomSerializer

* Adjust according to comment by @alpaca-tc

* Add language detection via WhatLanguage and (de)serialization of it through Atom

* Fix default language in ProcessFeedService

* Re-add newline before 'react-rails' Gem to fix groupings

Fixes Code Climate issue

* Remove trailing whitespace

* Use query methods instead of explicit .blank? checks

* Consolidate webfinger string creation under Account#to_webfinger_s

* Introduce Account#local_username_and_domain for consolidation

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.

* 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