Feature Request: Pass arbitrary options to the build actions

**Description:**
Based on experience building `claudia pack`, the team learnt that people kept wanting to add certain tweaks (eg skip the .npmrc file, skip security audits, don’t create package.lock etc). NPM keeps adding these steps into their builds. So they introduced the ability to pass arbitrary flags to NPM.

**Pros**: Easy to support these one off cases
**Cons**: This breaks one of the tenets - "make this builder super easy to reason about". Arbitrary flags make the builder hard to reason about because the output one person gets on his machine will be different from output another person get, because of the flags they have configured.

Ideally, we should implement 80% of these requested features in the build action. But I am opening this feature request to collect use cases for passing arbitrary options to build actions.

**Request by build actions**:
1. node-npm

Start by reading the node-npm build action and the issue's listed use cases. Determine which requested build options should be supported explicitly and how arbitrary options would be configured; done means the accepted scope and behavior are defined, with the trade-off between convenience and reproducibility resolved.

Written by the indexing model from the issue text.