* remove is_init_py of RandomGenerator, and use Global Generator if not OP seed

* fix comment

* fix beam search bug

* add dygraph unittest

* update dynamic_decode argument doc

* add warning info for state which has no lengths attribute

* update hapi predict interface

* fix code style

* fix docs

* fix docs

* fix docs

* update docs

* fix codes style

* fix unittest

* fix unittest

* fix coverage

* rename manual_seed to seed

* rename xxx1d-->xxx1D, xxx2d-->xxx2D, xxx3d-->xxx3D

* rename manual_seed --> seed

* do not rename .cc, .cu and .h file

* rename manual_seed --> seed

* rename manual_seed --> seed

* rename manual_seed --> seed

* rename manual_seed --> seed

* disable_static on doc example code

* donot change manual_seed on generator

* add enable_static on sample code

* convert python/paddle/fluid/layers/nn.py to bak

* fix typo

* fix code style

* fix seed to manual_seed when call functions of Generator()

* fix bug

* Make dynamic_decode support dygraph and expose to API 2.0
test=develop

* update info about BeamSearchDecoder and dynamic_decode

* remove all APIs in paddle.text, expose BeamSearchDecoder and dynamic_decode

* update example code

* delete test_text.py, decode.py, update some doc, fix example code float64

* delete decode import from paddle.nn

* fix unittest bugs

* use dygraph.Embedding instead of nn.Embedding, add paddle.enbale_static()

* update, correct doc

* move dynamic_decode, BeamSearchDecoder API to paddle.nn

* fix code style

* update unittest param, delete import pf text.py

* set dtype of beamsearchtest float64

* update example code of BeamSearchDecoder, dynamic_decode
Co-authored-by: NLiuChiaChi <709153940@qq.com>

* add div, floor_div, remainder

* Add support for dynamic_decode(while) training. test=develop

* Fix assign_op and tensor_array_read_write_op after solving conflict. test=develop

* Fix test_rnn_decode_api.py. test=develop

* Refine docs for apis in rnn.py. test=develop

* Adjust outputs of dynamic_decode. test=develop

* Remove the force_cpu update in assign_op. test=develop

* Remove the force_cpu update in assign_op. test=develop

* Make RNNCell.get_initial_states support batch_dim_idx argument. test=develop

* Rename _create_array_outof_while as _create_array_out_of_while in rnn.py.
test=develop