Update dependencies to latest, and avoid out-of-date minimatch sub-dependency.

[Standard8]

When installing the current version of node-virtualenv in my repository, I frequently see:

npm WARN deprecated [email protected]: Please update to minimatch 3.0.2 or higher to avoid a RegExp DoS issue

Although this might not affect node-virtualenv, it would still be good to get the dependencies of the published package updated so that we can avoid the warning.

I've generated the updates with npm 5.3.0, so I've added the package-lock.json as well (the whitespace changes to package.json where done by npm as well).

[BrainBacon]

LGTM