* Add the imperative quantization aware training.
*  This is the python part of Imperative QAT. test=develop

* fix softmax_with_cross_entropy cuda kernel overflow bug, test=develop

* replace old macro & for condition, test=develop

* polish details, test=develop

* add explicit specialization

* add skiplayernorm vector load if available

* test=develop

* polish pe exception process logic, test=develop

* fix unittest, test=develop

* add unittests, test=develop

Use vector instruction (LDG.128) to improve qkv transpose. It
provides 1.4X speedup at same GPU base frequency.
test=develop

remove useless property

test=develop

* fix concat shape error
test=develop

* add retry for prefetch

* Revert "Fix/sync barrier (#25016)"

This reverts commit be6a315f.

* reopen dist UT, test=develop

* remove fl UT, test=develop

* fix bn & in in dy, test=develop

* update instance_norm,test=develop

* fix bugs,test=develop

* add more case in unittest,test=develop

* fix,test=develop

* fix,test=develop

* add device_worker for pipeline, test=develop

* cat bad alloc exception; test=develop

* add unitest; test=develop

* move bad alloc catch to the first place; test=develop

* polish error message; test=develop

* polish error message; test=develop

* add mutex header; test=develop

* fix multhead matmul's instable
test=develop

* fix multihead matmul bug
test=develop

* fix converage problem
test=develop

* refine PADDLE_ENFORCE
test=develop

* add paddle.fleet.DistributedStrategy for 2.0

* modify pipeline optimizer, test=develop

* add mish op. test=develop

* fix PADDLE_ENFORCE and refine the description
test=develop

* Add `matrix_nms_op`

test=develop

* Make ci happy

test=develop

* Exit early when no detection

test=develop

* Fix license year

test=develop

* Output index as well

test=develop

* Match nms2 lod behavior and add `return_index` flag

test=develop

* Make CI happy

test=develop

* Fix wording

test=develop

* refactor dynamic dso search func, test=develop

* polish details, test=develop

* polish detail based review comments, test=develop

* revert string type change, test=develop

* add encrypt api for inference lib

* test=develop, fix_embedding

* Modify tmp var name prefix in dygraph test=develop

* refine comment test=develop