Marica Antonacci

@alberto-brigandi can we close this PR?

Hi all, the bintray URLs are still not working...any plans for making the packages available somewhere else? thanks

Hi @clintkitson, indeed I'm trying to enable external persistent volumes for Mesos tasks launched through Mesos containerizer as described [here](http://mesos.apache.org/documentation/latest/isolators/docker-volume/). I'm using Mesos containerizer (and not Docker containerizer) since I...

Moreover, in case of empty strings the field is converted to None