Hello everyone. Faced with error from issue title. "webpack-stats.json" file may be different depending on the version of npm's "webpack-bundle-tracker" module. Here is my solution for brothers in arms:

1. delete "node_modules" folder
2. edit "package.json" file: replace version of "webpack-bundle-tracker" with "^0.4.3" instead of "^1.0.0-alpha.1".
3. reinstall modules