Add support for subscriptions and scheduled actions in service config

Right now it is only possible to schedule actions and subscribe to events programatically. This is normally done in the service init() method. This is fine, but it means that you also have to handle the APPLICATION_ENV programatically if it is a factor. This is the case if you want to subscribe to an event in development only, to assist with development but you don't want to allow that in production.

We should be using the service config file to handle all this, that way the APPLICATION_ENV is always taken into account when loading the config and we can easily subscribe/schedule different things based on the environment.