Pipe curated feed search through the same infrastructure as regular feed search for providing relevance based searching. Fixes #867.
Fix up code analysis and tidy method interfaces.
Fix code review feedback, and a bug I just spotted where ad hoc ODATA queries would no longer be filtered to the correct curated feed package set.
Perf fix - revert CR fix. Package filter set must be passed as IQueryable for to avoid marshalling ALL package data from the database.
Merge pull request #884 from NuGet/tilovell-867

Relevance based curated feed search