Improve error and exception typing in python

bntsm

Hi dataiku team,

I am currently missing a feature: To develop python code around the dataiku package, it would be helpful to get more specific error types.

For example, the commonly used dataiku.Dataset, dataiku.Folder and dataiku.SQLExecutor2 currently return the general Exception for any error, while an AuthenticationError, FileNotFoundError, ValueError, etc. can be very useful for error handling and logging.