snf-deploy Use symbolic debian_base_url
For debian_base_url use a link that always resolvesto the latest image.
deploy: Modify dir for filebased email_backend
Allow user to modify the directory that willbe used for the filebased email backend by Django.
Also move the EMAIL_BACKEND option from astakos tocommon.
deploy: Install rabbitmq from Debian repos
Now that squeeze-backports has 2.8.4-1~bpo60+1 andwheezy has 2.8.4-1 version we can install rabbitmq-serverfrom the official Debian repos.
ci: Support wheezy installation