Provide production dependencies to the Webpack configs

[DimitarTachev]

Is your feature request related to a problem? Please describe.
I need to post-process the production npm dependencies in the webpack.config.js file. As the CLI already has this knowledge, it will be nice if we can get them through the env object instead of calculating them once again.

Describe the solution you'd like
Pass the production dependencies array or a dependencies.json file path (if we hit the max params size) through the env object.