add support for FBT

[barakd]

Facebook FBT translations library seems very promising.
I was wondering if we can somehow add optional support to it in create-react-app projects,
Right now in order to use a project must be ejected in order to add the proper babel configuration.
If that's something you find reasonable to support, I'll be more than happy to write a PR for it given the right guidance on how you would approach adding such a support.
I wonder if we can come up with something similar to relay-macros solution.
Thanks

[petetnt]

Related: facebook/fbt#41