Naming the directory "choo" aborts installation

```
> npx create-choo-app choo
...
Installing packages, this might take a couple of minutes.
Installing choo, choo-service-worker, sheetify, and tachyons…

Aborting installation. The following error occured:
npm install --save --loglevel error choo choo-service-worker sheetify tachyons

Deleting generated file… package.json
Deleting generated file… node_modules
Cleanup completed, please try again sometime.
```

```
> npx --version
6.7.0
> sw_vers -productVersion
10.14.3

```