add libffi-dev, which is apparently needed for shade
add libffi-dev, which is apparently needed for shade

bcornec/bifrost,bcornec/bifrost,openstack/bifrost,devananda/bifrost,EntropyWorks/bifrost,openstack/bifrost,devananda/bifrost,juliakreger/bifrost,EntropyWorks/bifrost,juliakreger/bifrost