dillon1000/react

[rfc][babel] InvalidConfig always throws

When you have your panic threshold set to "NONE" as we recommend, it's easy to 
miss that your config is wrong (which makes everything not compile) because 
those errors were being silenced. This made debugging FluentUI and the 
forget-feedback testapp pretty difficult to figure out at first, and defeats the 
purpose of having config validation in the first place. 

This pr makes it so InvalidConfig errors always throw, regardless of the panic 
threshold set. In general our plugin should never throw at build time due to 
component bailouts, but because an InvalidConfig would bailout everything from 
being compiled at all, it seems reasonable to throw here