* expose peak gpu memory API to python test=develop

* add unittest for peak gpu memory monitoring test=develop

* add pybind change test=develop

* add mutex to gpu mem usage monitor test=develop

* update benchmark flag definition file test=develop

* tweak unittest for memory monitoring test=develop

test=develop

Add box clip op

test=develop

refine bert

* use mat attr and refine test

test=develop

* add matmul jitcode

test=develop

* fix mac compile

test=develop

* Add calibration README; test=develop

Yolo loss darknet

use embedding=128 bert model for test

* Add INT8 calibration support in Paddle package; test=develop

* Enable pool2d operator for a ngraph engine
test=develop

* Update
test=develop

test=develop, polish code and fix some wrong change

* move var strusted to vars_distributed.py, add optimizer's block name, test=develop

* rename optimzier's seems complex, revert it, test=develop

* replace * with details, test=develop

* Enable performance measurement in INT8 calibration unit test

test=develop

Make separate folders for mkldnn codes

* Some improvements to support bert mixed precision training

test=develop

* Revert the cast in layer_norm

test=develop

* Refine beam_search_op to output an extra parent_idx tensor.
test=develop

* Fix the unittest test_beam_search_op.
test=develop

* Fix the merging mistake.
test=develop

Add axis for boxcoder