Revert "Revert "Make `bosh int` fail without required `windows2016-cell.yml`""
Revert "Revert "Make `bosh int` fail without required `windows2016-cell.yml`""

This reverts commit e090101789f6b147de0f701f03fa238c358fde77.

cloudfoundry/cf-deployment,cloudfoundry/cf-deployment