upgrade api for rec_case

update fluid.layers.data to layers.data

* del left name_scope docs
test=develop

* minor fix
test=develop

* add explaination on model.eval(), test=develop

* follow comments, test=develop

* fix dead links for models

* fix_dead_links

update x2paddle link

* update DetectionMAP reference

* Update DetectionMAP_cn.rst

* update paddle version in DyGraph.md, test=develop

* update paddle version in DyGraph.md, test=develop

* Add picture for deploy_ctr_on_baidu_cloud_cn.rst

* Baidu yun K8S + Volcano CTR Training Document 1.0

* Add ctr_pserver_log.png for deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Add pserver-log

* Update deploy_ctr_on_baidu_cloud_cn.rst

* chanage image of kubectl download version from 1.13.3 to  1.13.4

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

Update on Sept 18. 
remove description of helm, tiller, Go install.
replace new yaml provided by Jinghui Zhang

* add some images

* Update deploy_ctr_on_baidu_cloud_cn.rst

add model output manipulation part

* Update deploy_ctr_on_baidu_cloud_cn.rst

* update deploy ctr on baidu cloud cn.rst

* auto convert from md

* Update deploy_ctr_on_baidu_cloud_cn.rst

* replace the overview.png

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Delete train_on_baidu_cloud_en.rst

it is outdated and cannot match with Chinese Version for months.

* Delete train_on_baidu_cloud_cn.rst

Has been replaced by ELASTIC CTR

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

* Update deploy_ctr_on_baidu_cloud_cn.rst

test=document_fix

* add cn docs, test=develop

* refine docs, test=develop

* add program doc, test=develop

* fix links, test=develop

* fix links, test=develop

* fix links, test=develop

* fix links, test=develop

* Fluid -> Paddle, test=develop

* Fluid -> Paddle, test=develop

* minor fix, test=develop

* minor fix, test=develop

* add save load save_dygraph load_dygraph, test=develop

* add .idea in gitignore, test=develop

* minor fix, test=develop

* doc refines, test=develop

* doc refines, test=develop

* add stop_gradient notes in Dygraph, test=develop

* add stop_gradient notes in Dygraph, test=develop

* polish code in Dygraph, test=develop

* polish code in Dygraph, test=develop

* polish code in Dygraph, test=develop

* add Automatic pruning in Dygraph, test=develop

* fix Dygraph cn sample code, test=develop

* fix Dygraph doc format, test=develop

new document to upload in this PR

the previous doc talks about how to run CTR training on Baidu Cloud K8S Cluster.

the new doc are modified in following points.

1.Run CTR Training on Baidu Cloud K8S + Huawei Volcano
2.Auto Split CTR model into sparse ones and dense ones.
3.Cube auto fetch Sparse model, Serving auto fetch dense model.
4.provide paddle serving client to test the ctr prediction.

* polish en doc of data_loader

* follow comments

* use fluid.data()

* refine prepare steps doc, test=develop

* replace layers.data with fluid.data, test=develop

* refine doc

* follow lanxiang's comments, test=develop

* add data-parallel model doc

* Polish DyGraph doc

Unify the guide content structure.

* fix typo in doc

* add faq for lod_tensor

* format the lod_tensor.rst

* fixed one error of api_cn

* fixed some errors of api_cn

* fixed some errors of api_cn

* fixed two errors.

* fixed two errors

* fixed one error.

* fixed one error

* fixed one error.

* fixed two errors.

* fixed one error.

* fixed two errors

* fixed two links

* synchronize api_cn with the api_en of develop.

* updated develop/api_cn

* update the api_cn of develop

* update api_cn of develop

* fixed some errors

* Delete .DS_Store

* Delete .DS_Store

* Delete .DS_Store

* Delete .DS_Store

* Delete .DS_Store

* fixed some wrong links

* fixed two links

* fixed two links and some error.

* fixed some errors.

* fixed two links

* http://newicafe.baidu.com/issue/DLTP-1771/show?from=page

* http://newicafe.baidu.com/issue/DLTP-1647/show?from=page

* http://newicafe.baidu.com/issue/DLTP-1529/show?from=page

* Update natural_exp_decay_cn.rst

* Update Reader_cn.rst

* http://newicafe.baidu.com/issue/DLTP-1907/show?from=page of develop

修改了DyGraph.md文件中加载图片的错误路径，使其与PaddleBook保持统一

* fixed one error of api_cn

* fixed some errors of api_cn

* fixed some errors of api_cn

* fixed two errors.

* fixed two errors

* fixed one error.

* fixed one error

* fixed one error.

* fixed two errors.

* fixed one error.

* fixed two errors

* fixed two links

* Update cluster_quick_start.rst

test=document_preview

test=document_preview