test=develop

list of fixed ops:
lookup_table_op
space_to_depth_op
squared_l2_distance_op
squared_l2_norm_op
teacher_student_sigmoid_loss_op
tree_conv_op
warpctc_op

test=develop

* test fuse all_reduce

test=develop

test=develop

* Try to enable the runtime_context_cache pass in train phase.

* Put the append of runtime_context_cache pass ahead of multi_dev passes.
test=develop

test=develop

test=develop

test=develop

test=develop

add NCCLParallelContext for parallel dygraph

test=develop

test=develop

test=develop

* add pixel_shuffle op

* add pixel_shuffle op, test=develop

* rewrite code, test=develop

* delete useless comment, test=develop

* Refine pixel_shuffle_op and unit testing

* refine code,test=develop

* refine .cu,test=develop

* fix unittest,test=develop

* Fix unit testing
test=develop

* resolve conflict, test=develop

* fix test, test=develop

* fix API, test=develop

* fix test datatype bug,test=develop

* polish comments,test=develop

* add API,test=develop

* test=develop

* Add Pixel_Shuffle OP,test=develop

* support python3,test=develop

* add include memory to travis CI bug,test=develop

test=develop
This reverts commit c38c7c56.

test=develop

* fix some grad op desc maker
test=develop

* fix grad op desc makers
test=develop

test=develop

* expose fuse broadcast ops

* Fix the bug of the fast threaded executor. I

test=develop

* fix preprocess script with processbar, integrity check and logs
test=develop

* delete unnecessary empty lines, change function name
test=develop

* Fix bug of gradient interface

* shrink transformer

* Right transformer

* Change from width-first backward to deep-first backward process

test=develop

* Reverse iterator op's input

test=develop

* Polish code

* Change the iteration direction in ingrads' map slots

test=develop

* Polish code

test=develop

* fix the bug of reusing different types of variables in memory_optimize_pass, test=develop

* disable SELECTED_ROWS AND LOD_TENSOR_ARRAY reusage, test=develop

* link the libwbaes.so into paddle

* polish detail, test=develop

* try fix mac_pr_ci error, test=develop

* add compile option, test=develop

* fix ci error, test=develop

* ignore failed to find mac lib, test=develop

* change cdn to bj, cdn can't get the latest version

* trigger ci, test=develop

* temporary delete win32 lib linking, test=develop

* change https to http, test=develop

* turn compile option on to off

* turn compile option off to on, test=develop

* try lib compiled by gcc4.8, test=develop

* update lib version, test=develop

* link other lib, test=develop

* add setup config

* delete false, test=develop

* delete no_soname, test=develop

* recover so name set

* fix, test=develop

* adjust make config, test=develop

* remove link to wbaes, test=develop

* remove useless define, test=develop

test=develop