internal object packages are no longer required
given gops depends on rsc.io/goversion/version now.
Also running dep prune to remove the packages
gops doesn't depend from the vendor directory.
Follow up of
112843115d (commitcomment-23936637)
Solves the problem of us having to manually watch
upstream and pull in bug fixes and updates, if our
internal copy goes stale.
Fixes#22.