Yaml parser can't parse JSON

According to http://www.yamllint.com/ the following is a valid `.yml` file.

``` yml
storage: /etc/acme
server: letsencrypt
certificates: [
    {
        "paths": {
            "/tmp": ["docs.example.org", "git.example.org"]
        }
    }
]
```

Instead of parsing successfully, the parser throws an exception.

```
Malformed inline YAML string [ at line 3 (near "certificates: [")
```
