* Post_training_quantizaion supports min_max methon

1. Rename AutoTracer to ProgramTranslator
2. Rename cached_program to program_cache
3. Remove some functor style __call__
4. Dict key should be string but not hash code of string

* add dequantize_log_op and make pyramid hash support int8 weight test=develop

* add unittest and update pyramid hash op test=develop

* remove paddle_enforce test=develop

* fix error message test=develop

* remove incorrent commit test=develop

* fix error message in log_dequantize test=develop

* change 2019 to 2020 test=develop

* remove useless check_grad test=develop

* sequential reader stage 1, test=develop

* fix ut, test=develop

* fix iterable=False reset bug, add some logs and polish code, test=develop

* inference feed partial data, test=develop

* Turn on keep_order=True for test, test=develop

* enhance ut to test more cases, test=develop

* test commit for reverting

* Revert "test commit for reverting", test=develop

This reverts commit 80aef42e.

* add ut of merged and unmerged results, test=develop

* add more uts for coverages and add en doc of api, test=develop

* follow comments, test=develop

* change note style, test=develop

update embedding_eltwise_layernorm fuse pass and fused kernel, to support multi input

* add double grad implementation for dygraph, test=develop

* polish code, add uts, test=develop

* fix place bug, test=develop

* polish codes, add more uts for coverages, test=develop

* add no_grad_set, test=develop

* add star gan ut, test=develop

* follow comments, test=develop

As the title

* move __getitem__ to cpp

* bug fix

* add type check and gil release

* support negative step with omitted ends
test=develop

* code refine
test=develop

* bug fix
test=develop

* slice always return different pyobj
test=develop

* Support to use external function test=develop

* refine the parms of ast_to_func test=develop

* support to modify dict and list in while_loop test=develop

* polish code test=develop

* fix div zero test=develop

* fix div zero test=develop

* add hostdevice function test=develop

* add eps when is zero test=develop

1. Add support for Break and Continue in Dygraph to Static
2. Also add support for gast.Not in NodeTestTransformer
3. Also add support for logical op transformation in LoopTransformer

* don't add unregisterd attr, test=develop

* add some unittests,test=develop

This reverts commit 66fce9e8.

* Support and/or in controlFlow if test=develop

add approximation for gelu, default value is False (only kernel with eigen is added, remove code for computing gelu with MKLDNN temporarily)

test=develop

Fleet Parameter Server API Integrated

* Improved stability through the use of caching

test=develop

* fix style

test=develop

* Fix syntax error

test=develop

* Fix syntax error

test=develop

* Support Tensor.shape in control flow if/for/while and separate TensorShapeTransformer from BasicApiTransformer. test=develop

* remove the fill_constant_batch_size_like,  gaussian_random_batch_size_like and uniform_random_batch_size_like_cn three Op unittest 

* add transpose_flatten_concat_fuse_pass tests for gpu and trt, test=develop

* update test_inference_api.py, test=develop

* Support and/or in controlFlow if test=develop

* Refine IsControlFlow interface test=develop

* fix the travic ci problem

* add fusion group test for backward and refine code

* Support that the input(x) of stack api is a LoDTensorArray. test=develop

* Support that the input of concat api is a LoDTensorArray. test=develop

* Add tests to test stack/concat called in dygraph_to_static. test=develop