URI.extract is too strong, not limited to URLs, matched real text.
Same issue was present in language detector.

* Count all URLs in text as 23 characters flat, do not count domain part of usernames

* Add new status text counting logic to web UI

* Bring Toot button in line with counter

Both should use stringz I guess

* Use grapheme_length for character count

* Added support for configurable reserved usernames

* Added reserved usernames from mastodon issue 1355

* Fix reserved usernames

* Stricter whitelist rules

* Linting

* Added spec for blacklisting

* Test subdomain blacklist on domain whitelist

* No need to split

* Change spec name

* Fix #2119 - Whenever about to send a HTTP request, normalize the URI

* Add test for IDN request in FetchLinkCardService

* Perform IDN normalization on domains before they are stored in the DB

* Add `Presenters` group to SimpleCov configuration

* Move validators to app/validators, add to simplecov config

Federate spoiler_text using warning attribute on <content /> instead of a <category term="spoiler" />
Clean up schema file from accidental development migrations