Service interface which can be implemented to define an algorithm used to pick
resources to be merged. For each picker service, a separate ResourceProviderFactory
will be exposed at the MERGE_ROOT of the picker.
Service property name identifying the root path for the merged resources.
By convention, starts, with /mnt, although this is by no means required.
The value of this service property must be of type String and must not end
in a slash.
Service property name specifying whether the parent hierarchy is
traversed to check for hiding properties. If not specified this
property defaults to false. The value of this
property must be of type Boolean.