Update Laravel 4.1

Change the dependencies as there is no need to limit the illuminate/support version to 4.0.*.

Adding the following to composer.json allows this repo to be used instead with no issue.
```
    "repositories": [
        {
            "type": "git",
            "url": "git://github.com/DouglasMedeiros/tagcloud.git"
        }
    ]
```