Add versions to plugins in manifest

[peschee]

Is your feature request related to a problem? Please describe.

We have a custom docker image for our Gauge tests run in our CI environment. In that docker image, we're installing "pinned" versions of the plugins to ensure our builds are reproducible:

npx gauge install html-report --version 4.2.0

In development thought, Gauge plugins are being installed from the manifest.json:

{
  "Language": "js",
  "Plugins": ["html-report"]
}

Currently, there's no way to specify a version in the manifest. I would appreciate it if one could ensure everybody is getting the same versions of the plugins when installing and running gauge locally and installing the plugins based on a manifest.

Describe the solution you'd like

The manifest schema / format could be extended to support this, e.g.:

{
  "Language": "js",
  "Plugins": ["html-report@4.2.0"]
}

Describe alternatives you've considered

We could manually run the gauge install commands for the plugins in a postinstall script in NPM. This would render the Plugins portion of the manifest obsolete.