currently when a service is removed (Remove d-bus method) some of its properties are
cleared but its folder and files in STORAGEDIR are not deleted. This patch removes such
Immutable services have a .config file in STORAGEDIR, and if they have been connected at
least once they also have the same folder of mutable services: the Remove method will
delete the folder and force a re-provision of the service: this will act as a reset of the
service to its default.