doc[compatibility]:add doc ref in the README

- refer the harbor compatibility doc in the README
- add .md suffix to the README file under api/harbor

Signed-off-by: Steven Zou <szou@vmware.com>

README.md

@@ -48,6 +48,14 @@ Harbor is hosted by the [Cloud Native Computing Foundation](https://cncf.io) (CN
 
 * [Harbor RESTful API](https://editor.swagger.io/?url=https://raw.githubusercontent.com/goharbor/harbor/master/api/harbor/swagger.yaml): The APIs for most administrative operations of Harbor and can be used to perform integrations with Harbor programmatically.
 
+## Compatibility
+
+The [compatibility list](./docs/harbor_compatibility_list.md) document provides compatibility information for the Harbor components.
+
+- [Replication adapters](./docs/harbor_compatibility_list.md#Replication-Adapters)
+- [OIDC adapters](./docs/harbor_compatibility_list.md#OIDC-Adapters)
+- [Scanner adapters](./docs/harbor_compatibility_list.md#Scanner-Adapters)
+
 ## Install & Run
 
 **System requirements:**

api/harbor/README.md

@@ -0,0 +1,18 @@
+# References
+ 
+This file lists all the files that are referring the swagger yaml file.
+
+- Makefile
+  - `java -jar swagger-codegen-cli.jar generate -i api/harbor/swagger.yaml -l python -o harborclient`
+- README
+  - `Harbor RESTful API` in `API` section
+- docs/configure_swagger.md
+  - `https://raw.githubusercontent.com/goharbor/harbor/master/api/harbor/swagger.yaml`
+- make/photon/portal/Dockerfile
+  - `COPY ./api/harbor/swagger.yaml /build_dir`
+- tests/swaggerchecker.sh
+  - `HARBOR_SWAGGER_FILE="https://raw.githubusercontent.com/$TRAVIS_REPO_SLUG/$TRAVIS_COMMIT/api/harbor/swagger.yaml"`
+  - else `HARBOR_SWAGGER_FILE="https://raw.githubusercontent.com/$TRAVIS_PULL_REQUEST_SLUG/$TRAVIS_PULL_REQUEST_SHA/api/harbor/swagger.yaml"`
+
+
+**Notes:** Base path is the code repository root dir.