Package mac app installer

[jacktang]

Hello,

I clone code from this repo and try to build mac installer by run npm run package:mac. It hangs and I don't where the building logs. The whole output:

22:00 $ npm run package:mac

> ElectronAPIDemos@1.3.0 package:mac /Users/jacktang/Code/electron-api-demos
> electron-packager . --overwrite --platform=darwin --arch=x64 --out=out --icon=assets/app-icon/mac/app.icns --osx-sign.identity='Developer ID Application: GitHub' --extend-info=assets/mac/info.plist

Packaging app for platform darwin x64 using electron v1.6.8

• What operating system are you using?
  macOS Sierra 10.12.5
• What version of Node.js is on your system?
  v7.3.0

[codebytere]

This should be resolved on more recent versions.