update readme (#20)

Signed-off-by: Zhiwei Yin <[email protected]>

README.md

@@ -15,7 +15,22 @@ The MCE operator is required to be installed on the Hub cluster.
 kubectl apply -f ./configuration/klusterletconfig.yaml
 ```
 
+2. Apply a `AddOnDeploymentConfig` for add-ons working in hosted mode.
 
+```
+kubectl apply -f ./configuration/addonhostedconfig.yaml
+```
+
+3. Patch work-manager add-on to support hosted mode.
+
+```
+kubectl patch clustermanagementaddon work-manager --type merge -p '{"spec":{"supportedConfigs":[{"defaultConfig":{"name":"addon-hosted-config","namespace":"multicluster-engine"},"group":"addon.open-cluster-management.io","resource":"addondeploymentconfigs"}]}}'
+```
+or
+
+```
+kubectl apply -f ./configuration/workmanagercma.yaml
+```
 # Install Policy after MCE is installed
 
 ```