add README.md

cluster/libvirt-coreos/README.md

+# Kubernetes CoreOS cluster
+
+With this tutorial one creates a Kubernetes CoreOS cluster containing of one
+master and three minions (workers) running on `192.168.10.1`-`192.168.10.4`.
+
+For working correctly you need to create the directory addressed as `POOL_PATH` in
+`util.sh`:
+```
+$ sudo mkdir /var/lib/libvirt/images/kubernetes
+$ sudo chown -R $USER:$USER /var/lib/libvirt/images/kubernetes/
+```
+
+Then we follow the instructions in the main `kubernetes` directory.
+
+For debugging set `export UTIL_SH_DEBUG=1`.
+```
+$ export KUBERNETES_PROVIDER=libvirt-coreos
+$ make release-skip-tests
+$ ./cluster/kube-up.sh
+```
+
+To bring the cluster down again, execute:
+```
+$ ./cluster/kube-down.sh
+```
+
+Have fun!
+