Python Unit Tests for CSP

* Simple Channel Send and Receive test
* Daisy Chain test with 100 channels/Go ops

Fix rename de-ref bug

First timeline version

* add the type of tuple

* add lod_tensor to tuple

Add global_step in nn.py

Fix the compilation on CUDA 9.1/GCC 5.3

Fix incorrect mdrst

RST list should manually iterate the number or use #.

Correctly handling variable with batch dimension for math ops.

* Adding Python boilerplate code for Go op

* Add very basic test case

* Adding the python logic for go routine

* Fix syntax

* Changing test to notest

* Rename Routine to Go

* Combining GoGuard and Go in one class

* Modify test

* Adding fluid close channel

* Fixing __init__.py for calling fluid.go()

* Adding stubs for channel methods and updating test case

* Removing import *

* Adding imports from concurrency

* Initial commit of GO_OP (for varun)

* Creating local scopes and go through them

* Updated go op inputs persistability enforcement

* Add thread execution; compile failing though

* Fix go op

* Cleaned up Go op

* Fix yapf format issue

* Readd warp ctc dir for unit tests

* Updated make_channel, channel_send, channel_recv and channel_close

* Moved thread function to another method, update unit tests

* remove output var

* Add stubs for channel operators

* Updating concurrency with signatures

* Updated the signature with return status

* Fixed dtype in variables

* Updating stub of ChannelSend + add infershape

* Updating stub of ChannelRecv + add infershape

* Updated signature

* Adding the channel_create operator

* Merge channel send+receive ops

* Update concurrency tests using all operators

* Updating the create op with ChannelHolder

* Fix issues with channel_create_op

* Add the implementation for channel_close op

* Add channel close operator, fix channel close op

* Adding the channel_send op

* Comment channels C++ and Python code

* Concurrency python api comment fix

* Update unit test to add Status variable

* Adding channel receive operator

* Update concurrency test to demonstrate a complete CSP flow

* Fix clang-format issues

* Fixed "Out" parameter name

* Fixing merge conflict in framework.py

* Add channel ops to framework.py no_kernel_op_set

* Seperating channel_send and channel_recv operators

* Documenting capacity type

* Update concurrency test to create go block as child block of main program

* Changing set status implementation

Registry var type infer in split_selected_rows op

Refine Sum in elementwise_op_function

* add async sgd document

* fix ci

* update by comment

* update doc

* fix ssd problems

* fix box decoder op

* fix dimension problem in detection tests

* update detection doc

* Update detection doc

* Update detection doc

* update detection doc

* update detection doc

adjust the structure of documentation (en)

parallel-do should not merge the gradient of parameter that stop_gradient=True

* Make CUPTI_LIB_PATH not passing by macro.
* Add missing header

Merge branch 'feature/parallel_nccl_not_support_batchnorm' of https://github.com/reyoung/Paddle into fix-parallel-do-with-non-parameter

Fix the profiler's bug in multi-gpu mode

Fix rename_var de-ref

refine FQA doc