[Enhancement] Refine GlobalAccessble (#144)

* rename global accessible and intergration get_sintance and create_instance

* move ManagerMixin to utils

* fix as docstring and seporate get_instance to get_instance and get_current_instance

* fix lint

* fix docstring, rename and move test_global_meta

* fix manager's runtime error description

fix manager's runtime error description

* Add comments

* Add comments