Giveaway system

[srnyx]

Made through ephemeral embeds with buttons to go onto the next/previous step and to finish/cancel.

• [ ] Requirements (roles, server, nickname, etc...)
• [ ] Use Discord timestamps for the timer
• [ ] Giveaway list command to list all current giveaways (usable by anyone)
• [ ] Basically whatever else other giveaway bots have (such as https://dasu.gg)