The package in npm contains a compiled example

Hey. Thanks for the helpful package.

Examining the size of `node_modules`, I noticed that the package in npm contains the `example/android/app/build` directory of ~ 190Mb in size.
I think it would be great to add the `example/ios/build` and `example/android/app/build` directories to `.gitignore`, which is used by `npm` by default to exclude files from the published package.

Thanks and have a nice day.