Railtie deprecation warning 'Initialization autoloaded the constant MagicLinks::UrlHelper'

[wozza35]

The railtie is including the UrlHelper inside an 'action controller loaded' hook.

Initialization is a one-off process. Because the files in an engine are automatically added to Rails' autoload paths, the UrlHelper is marked for hot reloading. As the initialization only happens once, we shouldn't be including the helper in an initializer like we do currently. Any changes to the helper will not update the code in ActionController.

Wrapping the inclusion of the helper in a to_prepare block will ensure the railtie codeis rerun after a hotreload. This will prevent any potentially issues during development and remove the deprecation warning.