Large Pool + Modifier Content Performance Improvements

Individual commits have more details but two problems uncovered, both related to modifier content which indicates that it "modifies" some other product ID. If you have an entitlement for that product ID, the content gets enabled, if you don't, we skip it.

In some cases it was discovered that the single entitlement being granted had content which modifies another product ID also in the entitlement. In this case we did the bind, then immediately flagged the entitlement just created for regeneration the next time the system asked for entitlements/serials. Thus a subscription-manager bind would actually generate the cert twice. (25s a pop for this particular SKU)

Second fix dramatically improves the performance when there are large numbers of content sets that modify product IDs, but calculating the list of all product IDs the consumer is entitled to once, instead of querying the database twice per content set per product that it appears on.