* 1. add -o command for pipeline;
2. remove basemode config;
3. add example configs for pphuman.

* copyright to Copyright

* 1. update docs for quick start;
2. delete merge_model_dir;
3. move cfg codes to cfg_utils.py

* Update QUICK_STARTED.md

* Update PPVehicle_QUICK_STARTED.md

* Update pphuman_action.md

* Update pphuman_action_en.md

* Update pphuman_attribute.md

* Update pphuman_attribute_en.md

* Update cfg_utils.py

* given inference model path, download model automatically

* encapsulate auto download model as a function

* given note that default model dir is download link

* change attr model download path to https://bj.bcebos.com/v1/paddledet/models/pipeline/PPLCNet_x1_0_person_attribute_945_infer.zip

* add ocsort tracker

* add ocsort deploy

* merge develop

* fix ocsort tracker codes

* fix doc, test=document_fix

* fix doc, test=document_fix

* attribute docs update

* fix mtmct

* update docs

* add docs, still in working

* add action doc

* add action en doc