* add save model for step

* add PS/Collective support , add definition in yaml.md

* add check for QueueDataset while saving by step, modify dnn config yaml as an example

* add logging about model save operation

* fix bug for adding check for QueueDataset, modify dnn config yaml

* fix bug for dnn model config yaml

* fix bug for checking QueueDataset

* fix UT fail

* fix UT fail
Co-authored-by: Ntangwei12 <tangwei12@baidu.com>

* add fine tuning trainer

* add doc

* fix
Co-authored-by: NseiriosPlus <tangwei12@baidu.com>
Co-authored-by: Nwuzhihua <35824027+fuyinno4@users.noreply.github.com>

* fix error ASCII

* fix doc error, delete custer reader md

* fix setup.py

* fix install/readme

* fix listwise

* fix travis

* fix readme
Co-authored-by: NseiriosPlus <tangwei12@baidu.com>

* fix readme.md

* fix README.md

* fix README.md

* fix readme

* fix readme

* fix

* fix widedeeep
Co-authored-by: Noverlordmax <515704170@qq.com>
Co-authored-by: Ntangwei12 <tangwei12@baidu.com>

* update

* fix

* delete ps-memory

* fix

* fix

* add cluster support

* add rank model BST

* update readme

* fix AutoInt

* bug fix

* add dien in rank models

* update readme

* fix esmm

* single infer -> infer

* fix increment folder repeated
Co-authored-by: Ntangwei <tangwei12@baidu.com>

* fix setup

* fix bug for dssm reader

* fix net bug at PY3 for afm


* fix multi cards with files

* fix ctr

* add validation

* add validation

* add validation

* fix compile

* fix ci

* fix user define runner

* fix gnn reader at PY3

* fix fast yaml config at PY3
Co-authored-by: Ntangwei <tangwei12@baidu.com>

* add cluster running

* add k8s/paddle cloud

* fix local cluster without gpu

* define engine to train/infer/local_cluster_train/cluster_train

* fix gpu cluster wait

* fix bug for 2ps 2tr
Co-authored-by: Ntangwei <tangwei12@baidu.com>

* fix recall py3 bug
Co-authored-by: Ntangwei12 <tangwei12@baidu.com>