This update contains docker 1.12.1.

This update also makes available runc and containerd.

- Update docker to 1.12.1 (boo#996015, boo#995058)
- Package docker-proxy (boo#995620)

The following bugs were fixed:

- Reapply fix for boo#983015 (Limit*=infinity).
- Specify an "OCI" runtime for our runc package explicitly (boo#978260)
- setting iptables option on ppc64le works now (boo#988707)

The following tracked packaging changes are included:

- use gcc6-go instead of gcc5-go (boo#988408)
- Explicitly state the version dependencies for runC and containerd (boo#993847)
- remove kernel dependency (boo#987198)