2.9.0

Upgrade discord.js to 12.2.0 (#555)

* Upgrade discord.js to 12.2.0

* Use cache accessors in Discord client

* Replace sendMessage with send

* Use avatarURL method

* Update test stubs for discord.js 12

* Disconnect clients at end of tests

* Fix disabling webhook mentions when bot lacks permissions

2.8.1

2.8.0

2.7.2

2.7.1

2.6.2

2.6.1