Copy edits for typos

cluster/addons/README.md

@@ -6,7 +6,7 @@ Kubernetes clusters. The add-ons are visible through the API (they can be listed
 using ```kubectl```), but manipulation of these objects is discouraged because
 the system will bring them back to the original state, in particular:
 * if an add-on is stopped, it will be restarted automatically
-* if an add-on is rolling-updated (for Replication Controlers), the system will stop the new version and
+* if an add-on is rolling-updated (for Replication Controllers), the system will stop the new version and
   start the old one again (or perform rolling update to the old version, in the
   future).
 

cluster/addons/dns/README.md

@@ -164,7 +164,7 @@ If you see that, DNS is working correctly.
 
 ## How does it work?
 SkyDNS depends on etcd for what to serve, but it doesn't really need all of
-what etcd offers (at least not in the way we use it).  For simplicty, we run
+what etcd offers (at least not in the way we use it).  For simplicity, we run
 etcd and SkyDNS together in a pod, and we do not try to link etcd instances
 across replicas.  A helper container called [kube2sky](kube2sky/) also runs in
 the pod and acts a bridge between Kubernetes and SkyDNS.  It finds the

cluster/addons/dns/kube2sky/README.md

@@ -26,7 +26,7 @@ mutation (insertion or removal of a dns entry) before giving up and crashing.
 
 `--etcd-server`: The etcd server that is being used by skydns.
 
-`--kube_master_url`: URL of kubernetes master. Reuired if `--kubecfg_file` is not set.
+`--kube_master_url`: URL of kubernetes master. Required if `--kubecfg_file` is not set.
 
 `--kubecfg_file`: Path to kubecfg file that contains the master URL and tokens to authenticate with the master.