refactor: optimize plugins for angular treeshaking

BREAKING CHANGE: You can remove the plugin import from the app.module.ts because of the changed Inject decorator

src/@ionic-native/plugins/hot-code-push/index.ts

@@ -113,7 +113,9 @@ export interface HotCodePushEventData {
   repo: 'https://github.com/nordnet/cordova-hot-code-push',
   platforms: ['Android', 'iOS']
 })
-@Injectable()
+@Injectable({
+  providedIn: 'root'
+})
 export class HotCodePush extends IonicNativePlugin {
   /**
    * Show dialog with the request to update application through the Store (App Store or Google Play).