Use fs.existsSync instead of fs.statSync
Use fs.existsSync instead of fs.statSync

`fs.statSync` throws an error when the file passed to it doesn't yet
exist. `fs.existsSync` performs the job nicely.

https://nodejs.org/api/fs.html#fs_fs_statsync_path
https://nodejs.org/api/fs.html#fs_fs_existssync_path

pelias/whosonfirst,pelias/whosonfirst