* allow forwarding for multi scale inputs

* fixed PadBatch not working with multi scale input

* add faster_rcnn_r34_fpn_multiscaletest_1x_coco.yml

* fixed multi scale input checking for batch transforms (PadBatch)

* less scales and faster inference for multi scale test configuration file

* fixed retrieving im_id from multi-scale inputs

* add multi scale prediction boxes merging

* allow multi scale testing for tools/infer.py (actually trainer.predict method)

* add MultiscaleTestResize setting for TestReader

* use BBoxPostProcess.nms parameter for multi scale prediction NMS of CascadeRCNN

* add documentation for multi scale testing

* raise exception if the network architecture is not supported in multi scale test mode

* move documentation file

* add test case for multi scale test

* load pretrained weights from URL

* add image files for testing. use relative path for input images

* update documentation

* use isinstance for sequence type checking. add empty checking for samples sequence

* udpate verison require & fix typo

* add changelog

* fix operators typo

* fix mot typo, test=document_fix

Update README_cn.md

* fix use_gpu in deploy doc,  test=document_fix

* fix deploy doc, test=document_fix

* add kitti metric

* clean kitti metric code

* fix kitticars doc

* fix feature model cfgs

* add kitti metric

* update link to release/2.2

* add the config of fairmot_headtracking

* add flops

Besides removing unnecessary imports, this also fixes the missing logger module in test_architectures.py within the static directory.

* fix_install_docs

* fix_install_docs2

* add document for keypoint dataset preparation

* test=document_fix

* test=document_fix

* 关键点文档中json示例格式化显示，test=document_fix

* add doc

* add FAQ

* update 2.1 readme

* update en doc, test=document_fix

* update doc, test=document_fix
Co-authored-by: NGuanghua Yu <742925032@qq.com>

* fix jde negative coords

* update jde model zoo

* describe format for some txt, test=document_fix

* fix mot doc

* remove image_lists, fix all mot docs, add custom data

* fix doc, test=document_fix

* fix dov

* fix doc format, test=document_fix

* update install docs

* fix slim doc,test=document_fix

* add config for jde and deepsort, add engine metric tools

* add mot_metrics

* fix configs engine and others

* fix configs others

* move configs

* fix ap_per_class, fix doc

* fix test_mode, seqs

* fix test_mode to metric

* fix JDE arch metric

* clean requirement

* add to requirement

* add inference benchmark

* add mot data

* fix operators, source

* fix data source transform

* fix parse_dataset register_op

* fix scale_factor, RandomAffine

* add assert for check

* fix ci

* add lite demo