Add support for default injection of attributes defined by interface

small contribution to provide a default behavior in Afterburner to inject fields which type is an interface. For interfaces only, a delegation to ServiceLoader (standard servie-provider mechanism of JRE) is performed.

Of course this could be achieved externally by setting a home made InstanceSupplier to the Injector.
I found valuable to provide a default behavior for interfaces injection, so here it is.