We need to modify so prebuildify also builds for 32 bit if this is the case. Linux and Windows.

For each platform-arch we will build two binaries, so if we build for x64 only on mac, linux and windows the resulting prebuilds/ folder will look like:

$ tree
.
├── darwin-x64
│   ├── electron-napi.node
│   └── node-napi.node
├── linux-x64
│   ├── electron-napi.node
│   └── node-napi.node
└── win32-x64
    ├── electron-napi.node
    └── node-napi.node

How common is 32 bit? Will people cry on windows? Personally I'd go for the above setup.