* Refine previous version RL codes

* Polish utils/__init__.py

* Draft

* Use | instead of Union

* Simulator & action interpreter

* Test passed

* Migrate to SAOEState & new qlib interpreter

* Black format

* . Revert file_storage change

* Refactor file structure & renaming functions

* Enrich test cases

* Add QlibIntradayBacktestData

* Test interpreter

* Black format

* .

.

.

* Rename receive_execute_result()

* Use indicator to simplify state update

* Format code

* Modify data path

* Adjust file structure

* Minor change

* Add copyright message

* Format code

* Rename util functions

* Add CI

* Pylint issue

* Remove useless code to pass pylint

* Pass mypy

* Mypy issue

* mypy issue

* mypy issue

* Revert "mypy issue"

This reverts commit 8eb1b01.

* mypy issue

* mypy issue

* Fix the numpy version incompatible bug

* Fix a minor typing issue

* Try to skip python 3.7 test for qlib simulator

* Resolve PR comments by Yuge; solve several CI issues.

* Black issue

* Fix a low-level type error

* Change data name

* Resolve PR comments. Leave TODOs in the code base.

Co-authored-by: Young <afe.young@gmail.com>