npm package for 4.0.0-alpha.3 has wrong 'main' field in package.json

[vit-lebediev]

npm package for 4.0.0-alpha.3 is missing ./dist/js/npm.js file, while it is specified as entry point in package.json ('main' field).

This, for example, causes node-resolve to fail when trying to resolve bootstrap.

This was introduces by PR #20072, but as I understand, author just forgot to change entry point.

This bug is really frustrating, as it stops people from using latest bootstrap with e.g. this great Angular2 tutorial: PatrickJS/PatrickJS-starter#215

[cvrebert]

Duplicate of #20383