Add a Docker example for running Riak.
Reformat Gentoo install instructions to 80 columns
Update Gentoo docs to reflect the package name change from app-emulation/lxc-docker to app-emulation/docker as discussed in today's #docker-meeting
Push tags to registry even if images are already uploaded
Merge pull request #1833 from shin-/1815-always-push-tags

Push tags to registry even if images are already uploaded
Merge pull request #1807 from tianon/gentoo-docs

Update Gentoo docs to reflect the package name change from app-emulation/lxc-docker to app-emulation/docker
Merge pull request #1773 from hectcastro/hc-riak-example

Add a Docker example for running Riak