Merge branch 'develop' of https://github.com/PaddlePaddle/Paddle into feature/combine_open_files_and_double_buffer

Port py3

Hide internal API of LoDTensors, Clipping, etc.

Move six.moves.queue to Queue

introduce libxsmm

reserve vector space before loop in top-k

* refine multi-thread CPU Parallel exe

* refine multi thread CPU Parallel exe

* Refine CPU version for ParallelExecutor

* add share_parameter_between_cards_

* Fix ParallelExecutor bug

* Fix unit test

* Fix parameter opt balance

* Fix with opti (param->grad)

* Add grad to op var

* Remove shard_param_between_cards

Hide internal API of LoDTensors, Clipping, etc.

Get BeamSearch Prob on C-API

simpilify distribute transpiler

Add Python Reader Op (Python side and unittests)

Distribute transpiler handle adam accumulator

fix bcast with parallel executor + cpu

Merge branch 'develop' of https://github.com/PaddlePaddle/Paddle into distribute-transpiler-handle-adam-accumulator

Merge branch 'complete_py_reader_python' of https://github.com/sneaxiy/Paddle into complete_py_reader_python

Merge branch 'complete_py_reader_python' of https://github.com/sneaxiy/Paddle into complete_py_reader_python

Throw all warnings from git describe in setup.py.in

Fix optimizer accumulator