Interface ReservationPolicy_PolicyValueMembers

1. Will try to launch instance in any reservation_ids if provided.
2. Will try to launch instance in any of the available capacity block.
3. Will try to launch instance in PAYG if 1 & 2 are not satisfied.

The instance is launched only using on-demand (PAYG) capacity. No attempt is made to find or use a Capacity Block. It's an error to provide reservation_ids with policy = FORBID

1. Will try to launch the instance in Capacity Blocks from reservation_ids if provided.
2. If reservation_ids are not provided will try to launch instance in suitable & available Capacity Block.
3. Fail otherwise.