WIP: Fix #209 missing component ref

[villesau]

Fixes https://github.com/heroku/react-refetch/issues/209 for most of the cases. For initial render the ref is still missing. But that's a problem mostly in case of mock data only I think. Proper fix for that would be to move fetch dispatching to componentDidMount instead of componentWillMount but that change might be controversial.

Also unified handling in case of values as I didn't see purpose to explicitly call then with custom logic as it's handled in createPromiseStateOnFulfillment anyways. If there is purpose, please let me know!

Also wondering what removes the component from meta if it's not defined in fetch calls then too.

TODO: tests