add README file

extension/encoding/cloudwatchencodingextension/README.md

@@ -0,0 +1,22 @@
+# Cloudwatch encoding extension
+
+<!-- status autogenerated section -->
+| Status        |           |
+| ------------- |-----------|
+| Stability     | [development]  |
+| Distributions | [] |
+| Issues        | [![Open issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aopen%20label%3Aextension%2Fcloudwatchencoding%20&label=open&color=orange&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aopen+is%3Aissue+label%3Aextension%2Fcloudwatchencoding) [![Closed issues](https://img.shields.io/github/issues-search/open-telemetry/opentelemetry-collector-contrib?query=is%3Aissue%20is%3Aclosed%20label%3Aextension%2Fcloudwatchencoding%20&label=closed&color=blue&logo=opentelemetry)](https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aclosed+is%3Aissue+label%3Aextension%2Fcloudwatchencoding) |
+| [Code Owners](https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/main/CONTRIBUTING.md#becoming-a-code-owner)    | [@constanca-m](https://www.github.com/constanca-m), [@axw](https://www.github.com/axw) |
+
+[development]: https://github.com/open-telemetry/opentelemetry-collector#development
+<!-- end autogenerated section -->
+
+The `cloudwatch_encoding` extension is used to unmarshal:
+- cloudwatch logs into `plogs.Log`, if used in a logs receiver
+- cloudwatch metrics into `pmetrics.Metric`, if used in a metrics receiver
+
+Example:
+```yaml
+extensions:
+  cloudwatch_encoding:
+```

extension/encoding/cloudwatchencodingextension/metadata.yaml

@@ -3,7 +3,7 @@ type: cloudwatch_encoding
 status:
   class: extension
   stability:
-    alpha: [extension]
+    development: [extension]
   distributions: []
   codeowners:
     active: [constanca-m, axw]