Slack Bot - Add slash command for requests

[#1]

I understand this isn't easy due to custom request queues etc., but it would be awesome if you could type /wf requests in slack and it'd give you the list of requests queues you have available. Then you'd select the request queue, and it'd give you the forms that you need to fill in just like in workfront.

We live in slack, and this would be slick to tell people just to use this slash command. Instead, we use the mobile app/website. I"m a bit afraid of the anti-pattern of someone going /wf add issue "help me" and adding it to our request queue projects, but this hasn't been an issue.