Auto-unreact feature

[ByemaxTheGamer]

When someone is picked in a giveaway their reaction is automatically removed from said giveaway (helps with rerolls). This feature can be used whenever u make a giveaway by adding "au" (or something else) after !gstart or as an option whenever you make a giveaway step-by-step

[Sanduhr32]

This might become an option when we implement slash commands.

[jagrosh]

With the current way we do giveaways, this won't be added. Once a giveaway ends, we don't store information about it anymore, so there would be no way for us to know to prevent which people from re-reacting to the message.

In the future, if we switch to a button-based implementation instead of a reaction-based one, we can possibly revisit this idea.

[jagrosh]

I think the best solution to this issue would be a boolean on the reroll command that includes/excludes existing winners