mysociety/popit — pull request #667 by struan (2014-10-31 12:49:47+00:00)
Title: Fix issues with deleting memberships

Not sure why this has stopped working but if you use .nin or $nin in a
where and then tack on a remove, or use them in a remove then it
produces an error about there being a $ in the key. To fix this do the
where then explicitely remove all the returned memberships.

Fixes #666