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.

contrib/recipes/README.md

@@ -3,3 +3,6 @@ Solutions to interesting problems and unique implementations that showcase the e
 
 - [Automated APIServer load balancing using Hipache and Fleet](docs/apiserver_hipache_registration.md)
 - [Jenkins-triggered rolling updates on sucessful "builds"](docs/rolling_updates_from_jenkins.md)
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contrib/recipes/docs/apiserver_hipache_registration.md

@@ -104,3 +104,6 @@ That's it! Fleet will schedule the apiserver on one of your minions and once it'
 twitter @jeefy
 
 irc.freenode.net #kubernetes jeefy
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contrib/recipes/docs/rolling_updates_from_jenkins.md

@@ -55,3 +55,6 @@ When using a private docker registry as we are, the Jenkins slaves as well as th
 twitter @jeefy
 
 irc.freenode.net #kubernetes jeefy
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+[![Analytics](https://kubernetes-site.appspot.com/UA-36037335-10/GitHub/contrib/recipes/docs/rolling_updates_from_jenkins.md?pixel)]()