Cornac 1.0.0

New models

• Neural Matrix Factorization (NeuMF) / Neural Collaborative Filtering (NCF) (#215)
• Generalized Matrix Factorization (GMF) (#216)
• Multi-Layer Perceptron (MLP) (#217)

New features and improvements

• Update VAECF model (#213)
• Add num_zeros argument into Dataset.uir_iter() to support negative sampling (#214)
• Add val_set into fit() function for model selection (#219)
• Support early stopping in Recommender (#220)
• Fix bug in read_text() function of reader (#221)
• Unify TrainSet and TestSet into single object Dataset (#222)
• Optimize evaluate() function in BaseMethod (#223)
• Dataset checks duplicate observations independently (#224)