Added api discovery to kubectl run, based on which we decide which generators to use

docs/user-guide/kubectl/kubectl_run.md

@@ -88,7 +88,7 @@ kubectl run pi --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print
       --dry-run[=false]: If true, only print the object that would be sent, without sending it.
       --env=[]: Environment variables to set in the container
       --expose[=false]: If true, a public, external service is created for the container(s) which are run
-      --generator="": The name of the API generator to use.  Default is 'deployment/v1beta1' if --restart=Always, otherwise the default is 'job/v1'.
+      --generator="": The name of the API generator to use.  Default is 'deployment/v1beta1' if --restart=Always, otherwise the default is 'job/v1'.  This will happen only for cluster version at least 1.2, for olders we will fallback to 'run/v1' for --restart=Alwyas, 'run-pod/v1' for others.
       --hostport=-1: The host port mapping for the container port. To demonstrate a single-machine container.
       --image="": The image for the container to run.
   -l, --labels="": Labels to apply to the pod(s).
@@ -147,7 +147,7 @@ kubectl run pi --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print
 
 * [kubectl](kubectl.md)	 - kubectl controls the Kubernetes cluster manager
 
-###### Auto generated by spf13/cobra on 29-Feb-2016
+###### Auto generated by spf13/cobra on 11-Mar-2016
 
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