Rename the OpenStack AWS resource to avoid name clash with native

OpenStack ships a native ASG resource type with the same name. We
rename this to AWSAutoScalingGroup to avoid the clash and make way
to the native type to come.
Add more Neutron resources, add validation and reorder

More resources have been added, some missing validation updated and
resources moved around for (mostly) more sane ordering where possible.
Fix our test to reflect the ASG name change
Add some notes about OpenStack in README.md
Merge pull request #63 from andybotting/openstack-update-validation

Openstack updates