Update README

Author: lambdalisue

README.md

@@ -1,16 +1,15 @@
 # azblob-upload-artifact
 
+![Test](https://github.com/fixpoint/azblob-upload-artifact/workflows/Test/badge.svg)
+
 This upload artifacts from your workflow to [Azure Blob Storage](https://azure.microsoft.com/ja-jp/services/storage/blobs/).
+It follows usage of [actions/upload-artifact](https://github.com/actions/upload-artifact) for easy migration.
 
 See also [azblob-download-artifact](https://github.com/fixpoint/azblob-download-artifact).
 
 ## Usage
 
-Get [Azure Storage connection strings](https://docs.microsoft.com/en-us/azure/storage/common/storage-configure-connection-string) and save it into secrets.
-
-See [action.yml](./action.yml)
-
-Basic:
+Get [Azure Storage connection strings](https://docs.microsoft.com/en-us/azure/storage/common/storage-configure-connection-string) and specify it to `connection-string` through Github secrets like:
 
 ```yaml
 steps:
@@ -20,13 +19,26 @@ steps:
 
   - run: echo hello > path/to/artifact/world.txt
 
-  - uses: fixpoint/azblob-upload-artifact@master
+  - uses: fixpoint/azblob-upload-artifact@v1
     with:
       connection-string: ${{ secrets.AZURE_STORAGE_CONNECTION_STRING }}
       name: my-artifact
       path: path/to/artifact
 ```
 
+To upload artifacts only when the previous step of a job failed, use `if: failure()`:
+
+```yaml
+- uses: fixpoint/azblob-upload-artifact@v1
+  if: failure()
+  with:
+    connection-string: ${{ secrets.AZURE_STORAGE_CONNECTION_STRING }}
+    name: my-artifact
+    path: path/to/artifact
+```
+
+See [action.yml](./action.yml) for more detail.
+
 ## License
 
 This scripts and documentation in this project are released under the [MIT License](./LICENSE).