cb0cat: version 20131216153906

`cb0cat` is a handy-dandy little cryptographic tool like `netcat` based on a Sponge function CBEAMr0, and is quite useful IMO.

There will likely be an update to the CBEAM function once the CAESAR deadline approaches, meaning the new version will be `cb1cat` (for CBEAMr1).

Despite that, I still offer this as a package.