Initial Variables required unnecesarily

First of all, nice project! I want to point out an issue I found recently. I tried implementing this in one of my projects but the Container wouldn't render so I ended up tracing the error to the componentWillMount lifecycle method of the Container, specifically to this line: https://github.com/RickWong/react-transmit/blob/master/src/lib/createContainer.js#L239. Going down that function call I noticed that this function returns false if the isRootContainer property of the Container is false, which in my case was because I hadn't declared initialVariables (https://github.com/RickWong/react-transmit/blob/master/src/lib/createContainer.js#L30). Once I set initialVariables to {} it worked as expected, but in my humble opinion that should have been uneccesary as I don't use any variables in my fragment functions. Or is this behaviour intended?

EDIT: Even if this behaviour is intended I don't think it should fail silently.