Add option to allow security context in local cluster

hack/local-up-cluster.sh

@@ -22,6 +22,7 @@ DOCKER_NATIVE=${DOCKER_NATIVE:-""}
 DOCKER=(docker ${DOCKER_OPTS})
 DOCKERIZE_KUBELET=${DOCKERIZE_KUBELET:-""}
 ALLOW_PRIVILEGED=${ALLOW_PRIVILEGED:-""}
+ALLOW_SECURITY_CONTEXT=${ALLOW_SECURITY_CONTEXT:-""}
 RUNTIME_CONFIG=${RUNTIME_CONFIG:-""}
 KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
 cd "${KUBE_ROOT}"
@@ -201,7 +202,11 @@ function set_service_accounts {
 
 function start_apiserver {
     # Admission Controllers to invoke prior to persisting objects in cluster
+    if [[ -z "${ALLOW_SECURITY_CONTEXT}" ]]; then
       ADMISSION_CONTROL=NamespaceLifecycle,NamespaceAutoProvision,LimitRanger,SecurityContextDeny,ServiceAccount,DenyEscalatingExec,ResourceQuota
+    else
+      ADMISSION_CONTROL=NamespaceLifecycle,NamespaceAutoProvision,LimitRanger,ServiceAccount,DenyEscalatingExec,ResourceQuota
+    fi
 
     # This is the default dir and filename where the apiserver will generate a self-signed cert
     # which should be able to be used as the CA to verify itself