PEP: Data

Data
  -> Model
        -> PythonModel
        -> LPyModel
        -> RModel
        -> ...
  -> BinaryData
  -> TextData

A model is a data with optional inputs and outputs and that can be run.

d = data(path)
data('img1.tiff')
-> Data('img1', 'img1.tiff', datatype='tiff')

d = Data(name, path, datatype)
d = Data('img1', 'ssh://...', datatype='tiff')