Revert upgrades

This PR reverts upgrades to KumaScript which we could not fully test due to not having sufficient content on staging.  Since we haven't implemented this in production, and have other bugs to fix, reverting seems like the only option.  

I've not done a revert like this before, but what I did was go down the history and back out the upgrades.  Let me know if I've done this wrong.

https://github.com/mozilla/kumascript/commits/master