[Tests] up to `node` `v8.2`, `v7.10`, `v6.11`, `v4.8`; improve matrix; newer npm breaks on older node
[Tests] up to `node` `v8.2`, `v7.10`, `v6.11`, `v4.8`; improve matrix; newer npm breaks on older node
ljharb/object.getownpropertydescriptors,es-shims/object.getownpropertydescriptors