added main entry to package.json

[jcteague]

I added an entry to package.jsonso that it can be imported from sass-module-loader

[lauriejones]

Hey mate, thanks for the PR. I was under the impression that main defaulted to index? Or is that not the case for .scss files?

[jcteague]

I didn't see anything in the package.json documentation to that effect. I can tell you I could not import using sass-module-loader without it explicitly stated in the package.json file.