Ability to pin threads

[harshhpareek]

Not being familiar with the codebase, I don't know if this is already implemented / easy to do so. The following kinds of threads should be pinned: Current open thread, Current meetup thread, Sequence reread threads, Monthly threads like the rationality quotes threads.

Recommendations for the future: Newbie threads, Diaspora threads (can be auto generated the way the rss-feeds thread on slack is), fundraising threads. Perhaps AMA-style threads with people who were once active but now have their own websites / preferred modes of communication

It is not clear that we have moderators who can be given the ability to pin/unpin threads. It seems anyone can submit these currently.