Updated puppet-neutron

We need Lukas' patch for empty subnets [1] and patch for ML2 resource duplication [2].

Fixes: rhbz#1096510

[1] https://github.com/stackforge/puppet-neutron/commit/78428c844f73bf585a8f8a3bdf615ba2a0e8983b
[2] https://github.com/stackforge/puppet-neutron/commit/66c436bc2f06c5a71d79c674697394a11ec227f9