Feature: invite other CodeBuddies to Discussion threads

[RuubixO]

Do you want to request a feature or report a bug?

Feature.

What is the current behavior?

None exists yet, but builds on other comments I've made in issues #1119, #1122, and #1123.

What is the expected behavior?

- Before I post the Discussion-thread:

1. Have a search bar--like the "Slack channel to notify"-- in-between the Topic and Tags boxes.
2. Show each desired CodeBuddy selected in an amendable list below the search box.
3. Each added CodeBuddy (guest) should have an x by their name so that I can remove them, if needed.
4. When I save the new Discussion and post it, each invitation should go out to that guest's email and slack Direct Messages, with a link to the Discussion thread.
5. The invitation should read, Hi there [guest], you've been invited to [Discussion-thread [TITLE]] by [CodeBuddies [NAME]]. Click this here to go to the thread!

- After I post the Discussion-thread:
If myself, another guest, or anyone browsing the Discussion thread on the CodeBuddies website would like to share this discussion with someone else, I would like the "Before" options above to be made available through a button in the left column of the thread under the unsubscribe box that says "add your friends and let them know about this cool discussion!"

[billglover]

I can see how this would give visibility to new discussions.

My concern with this proposal is that I don't want people to invite me to discussions. I prefer to opt-in to discussions, study groups and channels.

Would be interested to hear other views.