Qlib simulator refinement

[lihuoran]

Description

• Qlib Simulator
  • Use dict-like config to create strategies & executors. Totally abandon the hardcoded version.
  • Make Qlib simulator more general.
• Executor
  • Add is_collecting
  • Call inner_strategy.post_upper_level_exe_step() in NestedExecutor
• Strategy
  • Add post_upper_level_exe_step() method
  • Add SAOEStrategy, strategies that use SAOEState as states. Make DecomposedStrategy a subclass of SAOEStrategy.
  • Move StateMaintainer inside SAOEStrategy. Now each SAOEStrategy can have its own state maintainer, so it can maintain its own state.
• Other
  • Remove qlib/rl/from_neutrader. Move all necessary components into simulator_qlib.
  • Re-organize file structure
    • qlib/rl/strategy
    • qlib/rl/order_execution/objects
    • qlib/rl/order_execution/state

Motivation and Context

How Has This Been Tested?

• [ ] Pass the test by running: pytest qlib/tests/test_all_pipeline.py under upper directory of qlib.
• [ ] If you are adding a new feature, test on your own test scripts.

Screenshots of Test Results (if appropriate):

1. Pipeline test:
2. Your own tests:

Types of changes

• [ ] Fix bugs
• [ ] Add new feature
• [ ] Update documentation