[2255] The fetch method does not have a callback param.

In the documentation it states:

The fetch method is used to fill the store before rendering the page, it's like the asyncData method except it doesn't set the component data.

The asyncData has a callback for the case someone doesn't want to use promises, however the fetch method seems to lack this function parameter. I think the fetch method should be able to handle a callback with a possible error parameter even if it does not return any data.