* default cmvn compute config; more log of grad clip; diff ds2 cmvn compute and conf; ds2 lr step by epoch;

* fix ds2 config

* fix install and egs link

* sox speed pertrub shape (T, C), float64, process using int32

* fix libri ds2 scripts; add ngram and spm doc

* aishell ds2 cer7.86

* fix ds2 result

* ctc decoding weight 0.5

* tiny decoding conf

* more label of mergify

* format doc

* add cmvn and label smoothing loss layer

* add layer for transformer

* add glu and conformer conv

* add torch compatiable hack, mask funcs

* not hack size since it exists

* add test; attention

* add attention, common utils, hack paddle

* add audio utils

* conformer batch padding mask bug fix #223

* fix typo, python infer fix rnn mem opt name error and batchnorm1d, will be available at 2.0.2

* fix ci

* fix ci

* add encoder

* refactor egs

* add decoder

* refactor ctc, add ctc align, refactor ckpt, add warmup lr scheduler, cmvn utils

* refactor docs

* add fix

* fix readme

* fix bugs, refactor collator, add pad_sequence, fix ckpt bugs

* fix docstring

* refactor data feed order

* add u2 model

* refactor cmvn, test

* add utils

* add u2 config

* fix bugs

* fix bugs

* fix autograd maybe has problem when using inplace operation

* refactor data, build vocab; add format data

* fix text featurizer

* refactor build vocab

* add fbank, refactor feature of speech

* refactor audio feat

* refactor data preprare

* refactor data

* model init from config

* add u2 bins

* flake8

* can train

* fix bugs, add coverage, add scripts

* test can run

* fix data

* speed perturb with sox

* add spec aug

* fix for train

* fix train logitc

* fix logger

* log valid loss, time dataset process

* using np for speed perturb, remove some debug log of grad clip

* fix logger

* fix build vocab

* fix logger name

* using module logger as default

* fix

* fix install

* reorder imports

* fix board logger

* fix logger

* kaldi fbank and mfcc

* fix cmvn and print prarams

* fix add_eos_sos and cmvn

* fix cmvn compute

* fix logger and cmvn

* fix subsampling, label smoothing loss, remove useless

* add notebook test

* fix log

* fix tb logger

* multi gpu valid

* fix log

* fix log

* fix config

* fix compute cmvn, need paddle 2.1

* add cmvn notebook

* fix layer tools

* fix compute cmvn

* add rtf

* fix decoding

* fix layer tools

* fix log, add avg script

* more avg and test info

* fix dataset pickle problem; using 2.1 paddle; num_workers can > 0; ckpt save in exp dir;fix setup.sh;

* add vimrc

* refactor tiny script, add transformer and stream conf

* spm demo; librisppech scripts and confs

* fix log

* add librispeech scripts

* refactor data pipe; fix conf; fix u2 default params

* fix bugs

* refactor aishell scripts

* fix test

* fix cmvn

* fix s0 scripts

* fix ds2 scripts and bugs

* fix dev & test dataset filter

* fix dataset filter

* filter dev

* fix ckpt path

* filter test, since librispeech will cause OOM, but all test wer will be worse, since mismatch train with test

* add comment

* add syllable doc

* fix ds2 configs

* add doc

* add pypinyin tools

* fix decoder using blank_id=0

* mmseg with pybind11

* format code