Add D-Bus interfaces for remote resource management.
Defines two new D-Bus interfaces for data source object paths:
org.gnome.evolution.dataserver.Source.RemoteCreatable
Create() - creates a remote resource
org.gnome.evolution.dataserver.Source.RemoteDeletable
Delete() - deletes a remote resource
These methods will be invoked through ESource objects on the client
side. On the server side, the corresponding EServerSideSource will
receive the method invocation, but forward to an ECollectionBackend
to perform the actual operation.