Implement models for IMDB dataset

[kdassharma]

• Since it classifies good or bad, multinomial naive bayes might be an additional label to experiment with

[kdassharma]

• Logistic Regression Grid search cross-validation for hyperparameter tuning Gradient descent optimisation

• Decision Trees Pruning Grid search cross-validation for hyperparameter tuning

• Support vector machines Grid search cross-validation for hyperparameter tuning

• Ada boost Grid search cross-validation for hyperparameter tuning

• Random forest Grid search cross-validation for hyperparameter tuning