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* Prebuilt flask server images for faster image build
* More and better methods in Ebonite client
* Pipelines - chain Models methods into one Model-like objects
* Refactioring of image and instance API
* Rework of pandas DatasetType: now with column types, even non-primitive (e.g. datetimes)
* Helper functions for stanalone docker build/run
* Minor bugfixes and features