message: Update README with new instructions on how to configure the plugin.
diff: @@ -7,16 +7,38 @@ Website: [https://newrelic.com](https://newrelic.com)
  ## Getting Started
  -Add New Relic REST API Key to `app-config.yaml`
  +This plugin uses the Backstage proxy to securely communicate with New Relic's
  +APIs. Add the following to your `app-config.yaml` to enable this configuration:
  ```yaml
  -newrelic:
  - api:
  - baseUrl: 'https://api.newrelic.com/v2'
  - key: <NEW_RELIC_REST_API_KEY>
  +proxy:
  + '/newrelic/apm/api':
  + target: https://api.newrelic.com/v2
  + headers:
  + X-Api-Key:
  + $env: NEW_RELIC_REST_API_KEY
  ```
  -New Relic Plugin Path: [/newrelic](http://localhost:3000/newrelic)
  +In your production deployment of Backstage, you would also need to ensure that
  +you've set the `NEW_RELIC_REST_API_KEY` environment variable before starting
  +the backend.
  +
  +While working locally, you may wish to hard-code your API key in your
  +`app-config.local.yaml` like this:
  +
  +```yaml
  +# app-config.local.yaml
  +proxy:
  + 'newrelic/apm/api':
  + headers:
  + X-Api-Key: NRRA-YourActualApiKey
  +```
  +
  +Read more about how to find or generate this key in
  +[New Relic's Documentation](https://docs.newrelic.com/docs/apis/get-started/intro-apis/types-new-relic-api-keys#rest-api-key).
  +
  +See if it's working by visiting the New Relic Plugin Path:
  +[/newrelic](http://localhost:3000/newrelic)
  ## Features
  