Fix piping to commands by letting process exit naturally
Fix piping to commands by letting process exit naturally

[Node.js' `process.stdout` is asynchronous when connected to a
pipe](https://github.com/nodejs/node/blob/master/doc/api/process.md#a-note-on-process-io),
so forcing an earlier `process.exit()` results in incomplete data being
output to the pipe.

This fixes usecases like `cfcli ls -f json | json`.

danielpigott/cloudflare-cli