chore(coreos): upgrade to 379.3.0

This also bumps Docker to 1.1.1

Depends on https://github.com/deis/base/pull/8, as etcd is now 0.4.5 in these images. 

NOTE: This doesn't yet include new images for Rackspace or Amazon, but figured it was good to get into peoples' hands to test.

closes #1270