Feature/couch

A bunch of changes to support plain couchdb with mirrors
In 7dc648d43d255999c1ce347a73787bd0c0a3f910 you said in the commit message that the commenting out of the #raise was done temporarily. Was that commit temporary, and you want to put this back (in which case a rebase would be the cleaner way to deal with this), or was this something else (in which case, it might be good to have a more of an explanation in the commit message)