Merge pull request #2 from furykerry/master

update README for API usage

README.md

@@ -6,14 +6,35 @@ The canonical location of the Kruise Rollout API definition and client.
 
 | Kruise-Rollout-API |  Kruise-rollout  |
 |--------------------|------------------|
-| 0.4                | <= 0.4           | 
-| 0.5                |  0.5             |
+| 0.4.1                | <= 0.4           | 
+| 0.5.0                |  0.5             |
 
 ## Where does it come from?
 
 `kruise-rollout-api` is synced from [https://github.com/openkruise/rollouts/tree/master/api](https://github.com/openkruise/rollouts/tree/master/api).
 Code changes are made in that location, merged into `openkruise/rollouts` and later synced here.
 
+
+### How to get it
+
+To get the latest version, use go1.16+ and fetch using the `go get` command. For example:
+
+```
+go get github.com/openkruise/kruise-rollout-api@latest
+```
+
+To get a specific version, use go1.11+ and fetch the desired version using the `go get` command. For example:
+
+```
+go get github.com/openkruise/[email protected]
+```
+
+
+### How to use it
+
+please refer to the [example](examples/create-update-delete-rollout)
+
+
 ## Things you should NOT do
 
 [https://github.com/openkruise/rollouts/tree/master/api](https://github.com/openkruise/rollouts/tree/master/api) is synced to here.