* add demo code

* demo code review update: use BGR for pose model

* demo code review update 2

some data retrieving from cfg looks like retrieving from dict, some like from Namespace's instance or custom class' instance
"extra" is defined, why does the code ignore it later?

* Now can work with multiple person
* Don't need the docker
* Force people detection and pose estimation to be executed on same context (gpu or cpu)
* Add same example output

Add implementation of timm and modelscope.