Using ref with callbacks vs strings

[Sacha Greif]

Right now this codebase uses the ref="string" pattern a lot:

https://github.com/twisty/formsy-react-components/search?utf8=✓&q=ref

But the React docs mention this approach will be deprecated in favor of callbacks:

https://facebook.github.io/react/docs/more-about-refs.html

Also, for some weird reason string refs have been causing errors in certain situations, while callback refs don't. Would you consider a PR to replace the strings by callbacks?

[Tim Brayshaw]

Yes, go ahead!