This update pretty much rewrites most of the code

• Add support for slash commands
• Add support for multiple polls at once per server
• Add exit handling to log out of Discord when exiting
• Fix rich presence expiring after a while
• Change session reminder auto-update so it doesn't require a command
• Change reminder message to include the names of people in the session
• Change poll message to use seperate embeds per poll option
• Change from moment to luxon
• Update dependencies
• Possibly more things that I forgot (this was a big update)

BREAKING CHANGES:

The database structure changed. `data.json` will need deleting otherwise errors will likely occur

Command prefix is no longer a thing in `config.yml` as slash commands replace it