2.2.0 Support additional with hybrid benefits

• Support different with and without hybrid benefits instances: some instances are only available with or without hybrid benefits. I initially made the assumption that instances without hybrid benefits were a superset of instances with hybrid benefits. It turned out to be wrong.
• Discard duplicate VMs: due to what seems to be a user error, some instance names are duplicated. As I use instance names to identify VMs and match instances, this sort of broke everything. The easiest solution is to discard duplicate instances (later on I might try to discard only the incorrect one(s)). Unfortunately it means that the duplicate instances will be missing (better not to provide any price than an incorrect price).