Better handling of package.json main configuration

[Fatme]

Moved from NativeScript/nativescript-cli#670

@jlooper and I have run across a few different npm modules that have a "main" of "index" in their package.json, instead of "index.js"—for example https://github.com/Sembiance/email-validator and https://github.com/snoj/email-validation.

This difference means that using one of these modules requires you to do:

var validator = require("email-validator/index");

instead of

var validator = require("email-validator");

Can the NativeScript CLI be changed to assume the .js suffix when it is not present? Furthermore, I'd like the CLI to support modules that do not have a "main" in their package.json at all. In these cases the NativeScript CLI should just use that module's index.js (if present).

Thanks.

[Plamen5kov]

We already support index.js as "last resort"

[Plamen5kov]

now in package.json in attribute "main", it doesn't matter if you didn't specify the ".js" extension, because it will be added if missing.