Added product options to members segment select
Added product options to members segment select

refs https://github.com/TryGhost/Team/issues/800
refs https://github.com/TryGhost/Team/issues/802

- adds product segments to segment select component behind the feature flag
- This reverts commit c872130cfa44493a1b033cfc58ee3a16d4c93672

TryGhost/Ghost-Admin,TryGhost/Ghost-Admin