Add info about Docker 1.6 to README

CONTRIBUTING.adoc

@@ -35,7 +35,7 @@ Here's how to get set up:
 1. For Go, Git and optionally also Docker, follow the links below to get to installation information for these tools: +
 ** http://golang.org/doc/install[Installing Go]
 ** http://git-scm.com/book/en/v2/Getting-Started-Installing-Git[Installing Git]
-** https://docs.docker.com/installation/#installation[Installing Docker]
+** https://docs.docker.com/installation/#installation[Installing Docker]. NOTE: OpenShift now requires at least Docker 1.6. RPMs for Fedora and CentOS 7 are not yet available in the default yum repositories. If you're running Fedora or CentOS, please see the link:README.md#docker-16[README] for information on where to get Docker 1.6 RPMs for your platform.
 2. Next, create a Go workspace directory: +
 +
 ----

README.md

@@ -43,6 +43,30 @@ For more information on the security of containers, see these articles:
 Running untrusted containers will become less scary as improvements are made upstream to Docker and Kubernetes, but until then please be conscious of the images you run.  Consider using images from trusted parties, building them yourself on OpenShift, or only running containers that run as non-root users.
 
 
+Docker 1.6
+----------
+OpenShift now requires at least Docker 1.6. Here's how to get it:
+
+### Fedora 21
+RPMs for Docker 1.6 are available for Fedora 21 in the updates-testing yum repository. This is disabled by default, so you'll need to run the following command to install Docker 1.6:
+
+    sudo yum --enablerepo=updates-testing install docker-io
+
+If you're updating, replace `install` with `update` above.
+
+### CentOS 7
+Docker 1.6 is not yet available in the CentOS 7 Extras yum repository yet. In the meantime, you will need to install it from https://mirror.openshift.com/pub/openshift-v3/dependencies/centos7/x86_64/. Create `/etc/yum.repos.d/openshift-v3-dependencies.repo` with these contents
+
+    [openshift-v3-dependencies]
+    name=OpenShift V3 Dependencies
+    baseurl=https://mirror.openshift.com/pub/openshift-v3/dependencies/centos7/x86_64/
+    enabled=1
+    metadata_expire=7d
+    gpgcheck=0
+
+You will now be able to `yum install` or `yum update` Docker to 1.6.
+
+
 Getting Started
 ---------------
 The simplest way to run OpenShift Origin is in a Docker container: