Keep the newest cloud record per VM per month
Keep the newest cloud record per VM per month

- This is a halfway house between the pre-LRVM record loading and
  the LRVM record loading, where we keep multiple records for a
  VM (one per month) but take the newest record we receive per
  month.
- This makes it easier for sites to republish becuase they don't
  need to worry about the state of the repository.

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