use default namespace to do rollingupdate

[kazegusuri]

rollingupdate command uses namespace specified from resource file (such as redis.json) instead of current namespace, so the command fails except the default namespace.

$ kubectl --namespace=test create -f examples/guestbook-go/redis-master-controller.json
redis-master-controller

# modifiy examples/guestbook-go/redis-master-controller.json

$ kubectl --namespace=test rollingupdate redis-master-controller -f redis-master-controller.json
F0221 20:50:44.122863   17881 rollingupdate.go:99] replicationController "redis-master-controller" not found

$ kubectl --namespace=test get rc
CONTROLLER                CONTAINER(S)        IMAGE(S)            SELECTOR                 REPLICAS
redis-master-controller   redis-master        gurpartap/redis     name=redis,role=master   1

[zmerlynn]

LGTM