Feature/jmbo 115 everlytic api

Adds buildout config settings and API settings for jmbo-everlytic. jmbo-everlytic is an API into the EverLytic mailing list service to add and remove contacts, and update their subscription status based on the "receive_email" setting on the "Member" model. A post_save and pre_delete signal on the Member class is used up to automatically create/delete users and manage their subscriptions on EverLytic.