* Support memory eager deletion on recurrent OP (#17710)

Test PaddingRNN on V100 GPU device.

Test configuration: large model, padding mode (which is the mode using recurrentOp), one GPU.
                   
GPU memory (MiB):   6414 (this PR)     vs   6837 (without this PR)
Speed (steps/s):         10.28 (this PR)    vs    9.89 (without this PR)

* Fix random test_recurrent_op failure (#18718)

The change includes 3 things:

1. Set CPU_NUM to 1 in the tests because the ParallelExecutor will print warning that CPU_NUM is not set and use default 1.

2. Old tests compare two RNNs, hand written simple RNN and same RNN built by Paddle, but initialized RNN weights in numpy random and Paddle random separately. Fixed it by setting weights and bias values.

3. Also set numpy random seed in the tests. Now the two RNNs diff can be smaller (rtol from 0.1, 0.2 to. 0.01) in the tests.

* update executor feed

* fix bug in Class MultiSlotDataGenerator's function _gen_str, test=develop (#18222)
* fix some bug when merge sparse embedding parameters, test=develop (#18223)
* fix communicator with pyreader (#18350)
* delete AllocatorFacade destructor  (#18606)
* fix distribute transpiler GRPC error code 4, RPC Deadline (#18984)
* merge pr #18441

* CHERRY_PICK 18941, 18860: TRT fp16 support.

test=release/1.5

* CHERRY_PICK 19213: Fix BUG: Mask RCNN inference diff When using AnalysisPredictor.
    1. fix affine channel fuse pass.
    2. fix condition block op.
    3. fix merge lod tensor op bug.
    4. fix memory optim cause by reset lod op.

    test=release/1.5

* add fusion_seqpool_cvm_concat test=develop

* simplify pass, test=develop

* fix code style, test=develop

* Add call stack info during runtime and compile time
test=develop

* add warning info for CPU_NUM
test=develop

* update dygraph parallel.py
test=develop

* prune the feed op in compiler
test=release/1.5

* remove compile from PE
test=develop

* test CUDAPinnedPlace in reader
test=release/1.5

* fix REGISTER_OP_WITHOUT_GRADIENT
test=develop

* fix backward bug

fix mask rcnn
add interface for setting optim_cache_dir(eg: when in trt int8 mode, and load model from memory, there should be a interface for setting the trt calibration table data dir)

test=release/1.5

* Update the Anakin interfaces for content-dnn and MLU (#17890)

* update anakin-engine interfaces for content-dnn

test=develop

* support only-gpu mode of Anakin

modify eltwise parse

test=develop

* modification for thread-safe

test=develop

* Integrated template instance

test=develop

* increase template parameters

test=develop

* support MLU predictor

test=develop

* update anakin cmake files

test=develop

* update TargetWrapper::set_device

* update the initialization of anakin subgraph

test=develop

* use the default constructor of base class

test=develop

* modify the access level of anakin engine (#18015)

test=develop

* fix ci test cmake test=develop

* update pe reduce config
test=release/1.5

*  drop the local_exe_scopes of the previous parallel_executor
test=release/1.5

test=release/1.5

test=release/1.5

* update execution_strategy option default value
test=release/1.5

* fix doc error
test=release/1.5

* remove nccl dep when the number of GPU is 1
test=develop

* use multi card run syncBN
test=release/1.5

Add trainer_desc proto DEPS to solve CI random fail.

cherry-pick for (https://github.com/PaddlePaddle/Paddle/pull/17402)

Add Pipeline Concurrency Train Mode:
- Cpp: pipeline_trainer & section_worker
- Python: PipelineOptimizer
- Add a new data_feed type: PrivateInstantDataFeed
- Add a test demo of pipeline trainer and the test model is gnn
- Do not support win32 now

* update CPU_NUM config
test=develop

* remove attribute in Allocator::Allocate, test=develop

* fix travis ci error, test=develop

* fix the ParallelExecutor on Windows
test=develop
* restrict to use one GPU only under windows

* delay infershape test=develop

* fall back subblock to paddle test=develop

* fix edge cases test=develop

* remove output duplicates test=develop

* handle reshape2_grad infershape test=develop

test=develop

test=develop

test=develop

* fix prepare context redundant code problem, optimize executor by caching create_varaiables
test=develop

* cache sub_scope, program, var when use_program_cache=True is set

* make fetch_list runable with variables, add more unittest for use_program_cache

* add event for fast executor and add threads for scopebuffer executor
test=develop

* Enhance fused_elementwise_activation op.
test=develop

* Move the api fused_elementwise_activation to contrib.
test=develop

* Add including files.
test=develop

* Add the support of sigmoid in fused_elementwise_activetion op.

* Update API.spec.
test=develop

* - changes to graph detector

- Changes to pass

- Added ut for new pass

- use_pass

- Added pass to mkldnn passes

- fix to registration

- improved verbose messaging for conv bias passes

- Lint fixes

test=develop

* - Lint fixes

test=develop

* add Concat quantization
add unit test for quantizing concat
fix for wrong value when the input is not in map of calculated scales
add use_quantizer to concat_op.cc
add scale_algo rules for concat

test=develop

* missing fix for multiple inputs quantize-squash

* wojtuss review fix: adding comment

test=develop