SageMaker Python SDK 1.1.0

• feature: Estimators: add support for TensorFlow-1.5.0
• feature: Estimators: add support for MXNet-1.0.0
• feature: Tests: use sagemaker_timestamp when creating endpoint names in integration tests
• feature: Session: print out billable seconds after training completes
• bug-fix: Estimators: fix LinearLearner and add unit tests
• bug-fix: Tests: fix timeouts for PCA async integration test
• feature: Predictors: allow predictor.predict() in the JSON serializer to accept dictionaries