no feedback

I'm running this inside a symfony2 repo where I'd normally run:

```
phpunit -c app
```

I created a config:

```
{
    "rootPath": ".",
    "fileOrDirectoriesToWatch": [
        "src"
    ],
    "commandArguments": [
        "-c",
        "app"
    ]
}
```

and it returns immedtiately without any error
