* [ppyolov3] add ppyolov3 base code

* add ppyolov3 s/m/x

* modify ema

* modify code to convert onnx successfully

* support arbitrary shape

* update config to use amp default

* refine ppyolo_head code

* modify reparameter code

* refine act layer

* adapter pico_head and tood_head code

* remove ppyolov3 yaml

* fix codestyle
Co-authored-by: Nwangxinxin08 <wangxinxin08@baidu.com>

* add a new version code of PicoDet

* add implementation of RetinaNet

* * add README.md and model zoo
* rename FOCSFeat -> RetianFeat
* add mstrain model to model zoo
* refactor DeltaBBoxCoder

* update link for model and log

* fix fuse_normalize not working when export model

* fix solov2 by keeping inputs setting before building model

* modify the ch_in&ch_out of the BasicBlock

(cherry picked from commit da568e4741f9a3a440ba1f605b8d12299fe4ed23)

* add the type convertion of the ch_in and ch_out & update gitignore

(cherry picked from commit 5b55097c6dab81dbccc187ba13a92b724ffc7ef5)

* revert the changes of gitignore

(cherry picked from commit ffeb72a8cefca6f416c5483756cc67f26f40522f)

This reverts commit 3e0e3585.

* support different norm_type for different module when convert to sync batch norm

* remove BatchNorm in esnet

* refine sync bn

* fix bugs of batch_norm

* fix bugs while deploying and modify BatchNorm to BatchNorm2D

* param_attr -> weight_attr in BatchNorm2D

* modify BatchNorm to BatchNorm2D

* fix assertion bug

* fix assertion bug

* add multi-scale test

* add resnet34-fpn-mstest item in model zoo

* update pptracking modelzoo readme

* fix cfg, test=document_fix

* fix label_list for mot, add warnings

* add result txt format, test=document_fix

* fix readme of mtmct, fix paddle.disable_static, test=document_fix

* remove paddle api

* fix problem of s2anet while deploying

* correct problem of s2anet TestReader

* add dota default category

* add mtmct aic_vehicle baseline

* fix clip_bbox, add coco model filter, fix some bugs

* fix infer bugs, fix crops and mtmct vis

* fix engine tracker infer

* fix mtmct images deploy

* fix readme and cfg

* remove mtmct of cfg modeling and tracker

* fix doc cfg

* fix Momentum and label list

* fix export of mcfairmot

* update citation

* update citation

* add mcfairmot train eval export code

* fix eval and export

* update modelzoo

* add hrnet18_dlafpn

* unify jdetracker

* fix deploy infer for single class

* fix multi class fairmot deploy

* fix mcmot data source and deploy

* fix num_identities

* fix num_identities_dict