Since the trunk scenario is now present in rally-openstack tree, it is no longer needed in neutron tree. Change-Id: I27c9f0baed267ca8bd181d34842b9d5cc03ab846
All *.py modules from this directory will be auto-loaded by Rally and all plugins will be discoverable. There is no need of any extra configuration and there is no difference between writing them here and in rally code base.
Note that it is better to push all interesting and useful benchmarks to Rally code base, this simplifies administration for Operators.