Add ga-beacon analytics to gendocs scripts

hack/run-gendocs.sh puts ga-beacon analytics link into all md files,
hack/verify-gendocs.sh verifies presence of link.

docs/getting-started-guides/coreos/azure/README.md

@@ -185,3 +185,6 @@ If you don't wish care about the Azure bill, you can tear down the cluster. It's
 > Note: make sure to use the _latest state file_, as after resizing there is a new one.
 
 By the way, with the scripts shown, you can deploy multiple clusters, if you like :)
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docs/getting-started-guides/coreos/bare_metal_offline.md

@@ -674,3 +674,6 @@ List Kubernetes
 Kill all pods:
 
     for i in `kubectl get pods | awk '{print $1}'`; do kubectl stop pod $i; done
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docs/getting-started-guides/coreos/coreos_multinode_cluster.md

@@ -132,3 +132,6 @@ hdiutil makehybrid -iso -joliet -joliet-volume-name "config-2" -joliet -o node.i
 #### Provision worker nodes
 
 Boot one or more the [vmware image](https://coreos.com/docs/running-coreos/platforms/vmware) using `node.iso` as a config drive.
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docs/getting-started-guides/coreos/coreos_single_node_cluster.md

@@ -56,3 +56,6 @@ hdiutil makehybrid -iso -joliet -joliet-volume-name "config-2" -joliet -o standa
 ```
 
 Boot the [vmware image](https://coreos.com/docs/running-coreos/platforms/vmware) using the `standalone.iso` as a config drive.
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