Support slash commands for adding users to the list?

[Verbina29]

This bot seems very useful, but the lack of slash commands is a bit of a dealbreaker. It'd also be cool if you could have it add anyone with a certain role or make it not restricted to admins.

[mcmonkey4eva]

• I'd welcome a PR for slash commands, I don't think I can justifying spending the time to develop them myself -- The difference between slash commands and @ commands is minor enough to not really matter as a difference to me personally.
• This first ever issue in the repo here has reminded me to add a project-status entry on the readme 676ecd6
• if you could have it add anyone with a certain role The original methods threadbot used to add users had issues with this type of control that wouldn't work, however the current method does! See details here 0d02089 including the new command to make use of it.
• or make it not restricted to admins. eh, sure, why not, added @ThreadBot adminrole (id) to mark a role of your choice as having access to bot-admin commands.