module: add API for identifying core modules

[jasnell]

There is userland code currently making unsafe use of
process.binding('natives') to identify core modules.
This points to an obvious need for a supported public
API. Let's provide one to discourage userland use of
private APIs

Userland example: https://github.com/facebook/jest/pull/4740/files#diff-240429220dd8540b70d06b165fc63ad3R5

/cc @bmeck @addaleax @bengl

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

Affected core subsystem(s)

modules

[cjihrig]

Perhaps this should be done as suggestions in #16386?

[jasnell]

I'd forgotten about that PR! I'll close this one and provide input on that one. Thanks :-)