Quick attempt to get pull requests passing

Accessibility Fix.

Add octodon.social

Add fern.surgeplay.com to the instances list

update social.targaryen.house info

Fix typo in ISSUE_TEMPLATE

Add instances from instances.mastodon.xyz

Fix typo in Heroku guide

More consistent typography

Create ISSUE_TEMPLATE.md to bring down duplicate issues

make regeneration worker unique, (only schedule/execute once at a time)

do not re-create a dynamic class on each feed push call, make sure redis-rb uses hiredis

must be added to the Sidekiq invokation in your systemd file

The pull queue will handle link crawling, thread resolving, and OStatus
processing. Such tasks are more likely to hang for a longer time (due to
network requests) so it is more sensible to not make the "in-house" tasks
wait for them.

eanable focus on ClearColumnButton

It's hard to tell if this is supposed to be alphabetically sorted or not. I put it after epiktistes since it starts with F - let me know if it should go elsewhere.