Adding DJ role handling

[LilyBergonzat]

Most music bots work with the concept of a DJ role that would have more permissions than regular members. For example, a regular member alone could not skip a song if multiple other people were listening to it, they would only be able to start a vote, while a DJ could be able to force skip a song.

Would it be possible to add the logic for that in the bot?

[Ch1sKey]

#65