* wip multi process multi gpu dist training

* workable for p2p

* update test=develop

* change back env name test=develop

* fix alloc init

* fix cpu build test=devlop

* fix mac tests test=develop

* refine code

* refine test=develop

test=develop

* refine cublase
test=develop

* code refine

* refine cublas

* add GEMME_EX

* add enable_cublas_tensor_op_math doc and add cublasCall
test=develop

* fix CublasCall for cuda version
test=develop

* fix error
test=develop

* fix GEMM_EX to be compatible with gcc 4.8
test=develop

* add GEMM_EX
test=develop

* to compatiable with gcc4.8
test=develop

Fix code to support cpplint syntax check

test=develop

test=develop

test=develop

This reverts commit 1d91a49d.

* some trivial opt

* remove the fix of lod_tensor and shrink_rnn_memory_op

* refine ShrinkRNNMemoryOp

test=develop

* Fix cpplint errors with paddle/fluid/platform/gpu_info.*

* Update

* "remove GPU Sync Interface"

* "fix typo"

* "fix type cast error"

* "fix related Copy with stream"

* "fix failed tests with DevicePool"

* "fix stupid removed position error"

* change GPU memory allocating policy

* fix potential overflow bug

* "fix accuracy kernel bug"

* "relauch ci"

* remove unused code

* fix cmake file

* fix build error