extract-intl / defineMessages

Hi, thanks for sharing this package!

Sorry, if I missed something, but is there, or will there be a way to extract a messages and build a translation.json files?

I mean something like what [react-boilerplate](https://github.com/react-boilerplate/react-boilerplate) do with command extract-intl ? Or what is recommendations to generate the files?

I may be wrong, but I checked the code and, it seems to me, that adding
[defineMessages](https://github.com/yahoo/react-intl/blob/master/src/define-messages.js) may make this project compatible with babel-plugin-react-intl, isn't it ?
The though is based on this [lines ](https://github.com/react-boilerplate/react-boilerplate/blob/master/internals/scripts/extract-intl.js#L103). Can we replace the name and get the results?

Best regards,

Review the referenced react-intl src/define-messages.js and react-boilerplate internals/scripts/extract-intl.js at line 103, then compare them with this package's existing message API. Clarify whether the goal is defineMessages compatibility, extraction, or translation.json generation; done would require an agreed scope and documented or tested behavior.

Written by the indexing model from the issue text.