Added portmap cni plugin

docs/09-bootstrapping-kubernetes-workers.md

@@ -79,10 +79,12 @@ POD_CIDR=$(curl -s -H "Metadata-Flavor: Google" \
 Create the `bridge` network configuration file:
 
 ```
-cat <<EOF | sudo tee /etc/cni/net.d/10-bridge.conf
+cat <<EOF | sudo tee /etc/cni/net.d/10-bridge.conflist
 {
   "cniVersion": "0.3.1",
   "name": "bridge",
+  "plugins": [
+    {
       "type": "bridge",
       "bridge": "cnio0",
       "isGateway": true,
@@ -94,6 +96,13 @@ cat <<EOF | sudo tee /etc/cni/net.d/10-bridge.conf
         ],
         "routes": [{"dst": "0.0.0.0/0"}]
       }
+    },
+    {
+      "type": "portmap",
+      "capabilities": {"portMappings": true},
+      "snat": true
+    }
+  ]
 }
 EOF
 ```