Merge pull request #38 from Clovel/fix/README

Updated README.md with instructions about code signing

Author: leo6104

README.md

@@ -50,7 +50,7 @@ npx cap sync
 
 With the Capacitor plugin installed, configure your app to use it via the following steps:
 
-1. Add your deployment keys to the `capacitor.config.json` file, making sure to include the right key:
+1. Add your deployment & code signing (optional) keys to the `capacitor.config.json` file, making sure to include the right key:
 
     ```json
     "Plugins": {
@@ -65,7 +65,16 @@ With the Capacitor plugin installed, configure your app to use it via the follow
     }
     ```
 
-    As a reminder, these keys are generated for you when you created your CodePush app via the CLI. If you need to retrieve them, you can simply run `appcenter codepush deployment list --app <ownerName>/<appName> --displayKeys`, and grab the key for the specific deployment you want to use (e.g. `Staging`, `Production`). App IDs can be retreived by running `appcenter apps list`.
+    As a reminder, the *deployment* keys are generated for you when you created your CodePush app via the CLI. If you need to retrieve them, you can simply run `appcenter codepush deployment list --app <ownerName>/<appName> --displayKeys`, and grab the key for the specific deployment you want to use (e.g. `Staging`, `Production`). App IDs can be retrieved by running `appcenter apps list`.
+
+    The *public* keys should be generated by you, as should the corresponding private keys.
+    ```bash
+    # generate private RSA key and write it to private.pem file
+    openssl genrsa -out private.pem
+
+    # export public key from private.pem into public.pem
+    openssl rsa -pubout -in private.pem -out public.pem
+    ```
 
     *NOTE: You [must](https://docs.microsoft.com/en-us/appcenter/distribution/codepush/cli#releasing-updates) create a separate CodePush app for iOS and Android, which is why the above sample illustrates declaring separate keys for Android and iOS. If you're only developing for a single platform, then you only need to specify the deployment key for either Android or iOS.*