Add link to pull images from a private Docker registry docs

README.md

@@ -149,7 +149,7 @@ Either way it provides access to the following fields:
 * **envVars** Environment variables that are applied to **ALL** containers.
     * **envVar** An environment variable whose value is defined inline.
     * **secretEnvVar** An environment variable whose value is derived from a Kubernetes secret.
-* **imagePullSecrets** List of pull secret names
+* **imagePullSecrets** List of pull secret names, to [pull images from a private Docker registry](https://kubernetes.io/docs/tasks/configure-pod-container/pull-image-private-registry/).
 * **annotations** Annotations to apply to the pod.
 * **inheritFrom** List of one or more pod templates to inherit from *(more details below)*.
 * **slaveConnectTimeout** Timeout in seconds for an agent to be online *(more details below)*.