Tensorflow and tensorboard versions update (lukalabs#58)

Big update: Keras, Tensorflow, Horovod, CuDNN (lukalabs#57)

Bumped requests (lukalabs#38)

Save and load weights separately for each model's param (lukalabs#25)

Cakechat refactoring (lukalabs#23)

CakeChat refactoring

Python 3 Compatibility (lukalabs#10)

* Python 2+3 compatibility

Pre-built Docker images (lukalabs#4)

* Update README to provide pre-built Docker images in Quick Start section.

CakeChat v1.0