Support empty strings

[smithtim]

Support empty strings

[joelittlejohn]

A thought about this: there are areas where empty strings are still not allowed, but I think we should avoid trying to identify these inside Faraday and just allow DynamoDB to throw an exception if these rules are broken. It seems safer to do this rather than get smart around whether an empty string should be allowed or not and in what context based on table metadata.

[kipz]

Thanks for the report @smithtim

I think it makes sense to add support for this. Is this something you'd be interested in contributing yourself?

[smithtim]

Okay, I've made a PR: #150

[joelittlejohn]

Fixed by #150