Build profile list before processing the item list.

With the following code:

```JavaScript
assetify.use(assetify.plugins.bundle);
assetify.compile({
    assets: {
        css: [{
            file: '/stylesheets/style.css',
            profile: 'core'
        }, {
            ext: '//fonts.googleapis.com/css?family=Open+Sans:400italic,700italic,400,700',
            profile: 'core'
        }, {
            file: '/stylesheets/font-awesome.css',
            profile: 'core'
        }],
        serve: false,
        explicit: true,
        source: path.join(rootDirectory, 'public'),
        bin: path.join(rootDirectory, 'public')
    }
}, function(error) {
    callback(error, app, rootDirectory);
});
```
And the middleware configured with:

```JavaScript
assetify(app, express, path.join(rootDirectory, 'public'));
```

The 'core' profile was not being output.

Pull request fixes this, for me at least.