Add documentation to setup delegate

Sources/Analytics/Analytics.docc/user-consent-article.md

@@ -61,3 +61,25 @@ extension AppDelegate: AnalyticsDataSource {
 In the example above user consent has been hardcoded but a real implementation should check local user consent data to provide parameters matching the current user choices.
 
 > Warning: ``AnalyticsDataSource`` methods are called with each event sent. Your implementation should therefore be as efficient as possible.
+
+### Setup an analytics delegate
+
+If you want to hook to analytics events to potential track something else like google analytics or blabla or blabla you can do like so:
+
+```swift
+final class AppDelegate: NSObject, UIApplicationDelegate {
+    func application(
+        _ application: UIApplication, 
+        didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil
+    ) -> Bool {
+        let configuration = Analytics.Configuration(
+            vendor: .SRF,
+            sourceKey: .productionSourceKey,
+            appSiteName: "app-site-name"
+        )
+        try? Analytics.shared.start(with: configuration, delegate: self)
+
+        // ...
+    }
+}
+```