Revert "Bump up bundled node 6 version to 6.16.0 (#2111)" (#2156)
Revert "Bump up bundled node 6 version to 6.16.0 (#2111)" (#2156)

This reverts commit 09d78f42273736258b0bf0727cab69c1fc9f4a6a.
Microsoft/vsts-agent,Microsoft/vsts-agent,Microsoft/vsts-agent,Microsoft/vsts-agent