* add doc & move code to cpp

* add check for track_model and det_model

* add model_dir as input

* unify log output

* add implementment for FlowStatics

* rename count to entrance_count; rename count_set to id_set

* add a todo for entrance line setting

* rename count to do_entrance_counting

* convert print_save_file to the origin line

* add stream input

* add stream input & add save_result

* add tracking pipeline

* move pptracking to deploy

* update according to review

* refine class define

* add yaml cmake