Change "main" indentifier
I'm have a style-guide app.  I want to drop in react-sketchapp to render to sketch.  I noticed that in package.json, the "main" property has end in ".sketchplugin" in order to work.  is there a way to use a different identifier property so I can keep my "main" : "index.js" ?  I tried changing the identifier in manifest.json but this didn't work.  

If not, do I have to maintain a separate sketchplugin package that has my style-guide as a dependency? What are some best practices ?