Add a clear pin link in the list topics view
Merge pull request #806 from ZogStriP/clear-pin-link-in-list-topics-view

Add a clear pin link in the list topics view
added setting to flush redis if you feel like doing so in dev
we can't trust CSRF for anon the way it is designed.
The page they have loaded may be cached we need a different way of delivering the CSRF potentially
deleting posts as an admin was bust