HACKING: Update documentation to reflect changes

 - Update documentation to reflect changes
 - Add note about how to work with the Fedora
Staging pipecfg.

Signed-off-by: Renata Ravanelli <rravanel@redhat.com>

Author: ravanelli

HACKING.md

@@ -532,12 +532,6 @@ using a development cluster, it normally isn't, and you can drop it. For
 the Fedora prod cluster, use `ocs-storagecluster-ceph-rbd` as shown
 above.
 
-If using an additional root CA certificate, then you will also need to
-specify the `AGENT_NAMESPACE` parameter to yours, e.g.:
-
-```
-  --param=AGENT_NAMESPACE=fedora-coreos-pipeline \
-```
 
 Now, create the Jenkins configmap:
 
@@ -586,6 +580,10 @@ This will create:
 3. the Jenkins agent BuildConfig (if a root CA cert was provided),
 4. the jenkins-config configmap.
 
+Note: If you are working with the Fedora staging pipeline, specify the
+`staging` branch for the pipecfg: `--pipecfg
+https://github.com/coreos/fedora-coreos-pipeline@staging`.
+
 If a root CA cert was provided, we need to build the base images that
 will bake in the cert in the controller and agent:
 
@@ -600,6 +598,12 @@ We can now start an S2I build of the Jenkins controller:
 oc start-build --follow jenkins-s2i
 ```
 
+If you added the root CA:
+```
+oc start-build jenkins-s2i --follow -e JENKINS_IMAGE_STREAM_TAG=upstream
+```
+
+
 Once the Jenkins controller image is built, Jenkins should start up (verify
 with `oc get pods`). Once the pod is marked READY, you should be able to
 login to the Jenkins UI at https://jenkins-$NAMESPACE.$CLUSTER_URL/