"Permission denied (publickey)"

I was unable to clone this as I got the following error:

```
$ git clone git@github.com:jarsbe/react-webpack-boilerplate.git app
Cloning into 'app'...
Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.
```

If it matters, I'm on OSX El Capitan (10.11.4).
Can you help me? Thank you!
