Because of the changing trt engine op from gpu to gpu mode.

(cherry-pick from commit 145b20c160329428c1ec05c94287708aa1ed6f63)

cherry-pick from commit 133ec696

(cherry picked from commit 1600ba86)

fix bug to avoid warning once import paddle.fluid

Merge pull request #12780 from panyx0718/ir4

fix sparse update bug

fix ProgramToGraph

(cherry picked from commit e525aa23)

Fix flowers dataset download problem

update native_infer.rst

Cherry pick add dependency to send recv

* dist transpiler add control dependency var between send and recv

* fix async deps

* follow comments and refine

* fix deps connect for rpc ops

Add dependency to send recv

* Disable in_place in batch_norm API.

Cherry pick rw lock

* add rw lock test

* optimize read_write and wirte_read test

Optimize selected rows for dist lookup table with rwlock 

This reverts commit bf3c3496.

disable anakin when cuda < 8.0 or cudnn < 7.0

add mklml depends for anakin

Sampling id op

Port print_function and make more efficient

Port pybind11 and python code to support py3 CI test

Add libpng dependencies to yum and correct libnccl dir

Refine gru cpu forward