Collapsing of closed and retracted comments.
Merge branch 'master' of https://github.com/wolftune/snowdrift into collapse

Conflicts:
	Handler/Discussion.hs
Merge branch 'master' of https://github.com/wolftune/snowdrift into collapse

Conflicts:
	Handler/Discussion.hs
invite.cassius was a file with no content. I don't know why it existed. Removing
some update to be more ready for testing
added section for setting up and running tests