Design portable file formats for models/datasets for import/export

[mattprintz]

A user should be able to generate a dojo model locally and then load it to a remote dojo server by exporting the local model and importing at the server.
A docker image could either be provided via a dockerhub image name (or alternative), or by using docker save to export a tar file.
The serialization should contain everything needed to recreate the model in the remote system, or to fully backup/restore a model.