* support visualdl in preprocess data

* support most preprocess op

test=document_fix

* update some link in README

* fix product news

* Update QUICK_STARTED_cn.md (#1757)

fix typo

* cherry-pick #1757 and #1473, test=document_fix

* update v0.5 release note

* update some comments

* add ppyolo_voc

* Add PrepareData-->SelectModel-->Train-->Eval-->Test-->Infer-->Slim-->Deploy document DetectionPipeline.md, test=document_fix

* Correct Format of README_en.md
* Update README_cn.md
* Correct details in README_en.md

* update solov2 some detail

* fix check paddle version

* update cpp build script

* rename document and update script

* set WITH_MKL=ON for pass CI

* set WITH_GPU=OFF and WITH_TENSORRT=OFF for pass CI

* check md5 before load weights.

* add TX2 cpp build document and benchmark

* turn WITH_MKL=ON

* add tensorrt version

* set WITH_GPU=OFF for CI

* keep same as TX2_build

* enhance voc to coco docs

* fix voc annotation float type

* add solov2_mobilenetv3

* update link on README

* use relative path

* add benchmark on win10 cpp finer, fix bug of _mkdir on windows VS2019 Release bulig

* win cpp use Predictor to inference

* 测试环境描述更加详细

* add enable_static()

* follow comments

* remove blank line