Add doc for OKE addons and node pool cycling (#290)

* Add doc for OKE addons and node pool cycling

Author: shyamradhakrishnan

docs/src/SUMMARY.md

@@ -40,6 +40,7 @@
   - [Virtual Nodes and Enhanced Clusters](./managed/virtual-nodes-and-enhanced-clusters.md)
   - [Boot volume expansion](./managed/boot-volume-expansion.md)
   - [Networking customizations](./managed/networking.md)
+  - [Features](./managed/features.md)
 - [Reference](./reference/reference.md)
   - [API Reference](./reference/api-reference.md)
     - [v1beta2 API](./reference/v1beta2-api.md)

docs/src/managed/features.md

@@ -0,0 +1,35 @@
+# Features
+
+This page will cover configuration of various Oracle Cloud Infrastructure Container Engine for Kubernetes (OKE) 
+features in CAPOCI.
+
+## Node Pool Cycling
+OKE [Node Pool Cycling][node-pool-cycling] can be used during Kubernetes version upgrades to cycle
+the nodes such that all the nodes of a Node Pool is running on the newer Kubernetes version. The following
+`OCIManagedMachinePool` spec can be used to specify Node Pool cycling option.
+```yaml
+apiVersion: infrastructure.cluster.x-k8s.io/v1beta2
+kind: OCIManagedMachinePool
+spec:
+  nodePoolCyclingDetails:
+    isNodeCyclingEnabled: true
+```
+
+## Addons
+The following `OCIManagedControlPlane` spec should  be used to specify [Addons][addons] which has to be
+installed in the OKE cluster.
+
+```yaml
+kind: OCIManagedControlPlane
+apiVersion: infrastructure.cluster.x-k8s.io/v1beta2
+spec:
+  clusterType: "ENHANCED_CLUSTER"
+  addons:
+  - name: CertManager
+```
+More details about the configuration parameters are available in [CAPOCI API Reference docs][api-reference].
+
+
+[node-pool-cycling]: https://docs.oracle.com/en-us/iaas/Content/ContEng/Tasks/contengupgradingk8sworkernode_topic-Performing_an_InPlace_Worker_Node_Upgrade_by_Cycling_an_Existing_Node_Pool.htm#contengupgradingk8sworkernode_topic-Performing_an_InPlace_Worker_Node_Upgrade_by_Cycling_an_Existing_Node_Pool
+[addons]: https://docs.oracle.com/en-us/iaas/Content/ContEng/Tasks/contengconfiguringclusteraddons.htm
+[api-docs]: ../reference/api-reference.md