Bug bash for release

[SparkSnail]

v1.6 bug bash

General Supports Updates

• TF 2.0 ENAS TensorFlow v2 Support #2127 @ultmaster (fixing import error)
• 100W IPC limitation @SparkSnail (fixing bug)
• share code storage among trials in an experiements @liuzhe-lz
• fix dev install @leckie-chn
• __version__ for SDK version @chicm-ms (need to fix issue)
• windows dev install @leckie-chn
• support windows as remote machine @SparkSnail

Web UI @chicm-ms

• finalize the homepage migration to readthedoc (homepage migration to readthedocs #2483 need to merge code)
  ----refine layout
• Show trial error message Show trial error message #2424
• Refactor overview top trials:
  related issue: webui pages are inconsistent #2007 Why not put the lastest result in the picture? #2010

HPO Updates

• PBT left work and improvement @colorjam (need to fix issue)

NAS Updates

• improvement NAS API, add readability, improve user experience @liuzhe-lz

Model Compression Updates

• Model compression PyTorch 1.4 support, utility codes merge Model compression PyTorch 1.4 support #2310 @colorjam (need to fix issue)

Training Service Updates @ultmaster

• support pai multiphase
• update pai yaml merge PAI Yaml merge #2309

[kvartet]

closed as it is overdue.