1. add a cmd script to generate sample config
2. set setup as False for generate_swagger, so we can make swagger
without skyline-apiserver yaml config
3. add make genconfig into Makefile
4. add config-sample-generator scripts into pyproject.toml
5. replace async with sync for generate_swagger script
6. add items, keys, values function for Group and Configuration
Change-Id: I4c7196f1d766a6abdc24c71c4b3135cd40cc26ef