Create hash of the model

[logankilpatrick]

Use the same infrastructure as is used for the UUID to make a hash of the model. This will allow us to maintain model integrity.

[asinghvi17]

Makes sense, but we probably shouldn't use the hash to address the model, only to maintain integrity. Hash will also have to be recomputed on overwrite.

[andreasnoack]

Are we talking about the model or the fit or both? Is the idea that you'd be able to compare two models to see if they are mathematically the same? I guess that might be challenging.