NNI v0.5.2 release

Release 0.5.2 - 3/4/2019

Improvements

• Curve fitting assessor performance improvement.

Documentation

• Chinese version document: https://nni.readthedocs.io/zh/latest/
• Debuggability/serviceability document: https://nni.readthedocs.io/en/latest/Tutorial/HowToDebug.html
• Tuner assessor reference: https://nni.readthedocs.io/en/latest/sdk_reference.html#tuner

Bug Fixes and Other Changes

• Fix a race condition bug that does not store trial job cancel status correctly.
• Fix search space parsing error when using SMAC tuner.
• Fix cifar10 example broken pipe issue.
• Add unit test cases for nnimanager and local training service.
• Add integration test azure pipelines for remote machine, PAI and kubeflow training services.
• Support Pylon in PAI webhdfs client.