Marker interface for all Service Component that wants to expose the Configuration through the ConfigurationService.
The Configuration Service tracks all OSGi Components which implement the
ConfigurableComponent marker
interface.
When a ConfigurableComponent is registered, the Configuration Service will call its "update"
method with the latest saved configuration as returned the ConfigurationAdmin or, if none
is available, with the Configuration properties fabricated from the default attribute values as
specified in the ObjectClassDefinition of this service.
In OSGi terms, this process in similar to the Auto Configuration Service.
The ConfigurationService assumes that Meta Type Information XML resource
for a given ConfigurableComponent with name abc" to be stored under OSGI-INF/metatype/abc.xml.
This is an extra restriction over the OSGi specification: the Meta Type Information XML resource
must be named as the name of the Declarative Service Component.