* Intermediate version
* Fix yaml template & Successfully run rolling
* Be compatible with benchmark
* Get same results with previous linear model
* Black formatting
* Update black
* Update the placeholder mechanism
* Update CI
* Update CI
* Upgrade Black
* Fix CI and simplify code
* Fix CI
* Move the data processing caching mechanism into utils.
* Adjusting DDG-DA
* Organize import
* modify FileStorage to support multiple freqs
* modify backtest's sample documentation
* change the logging level of read data exception from error to debug
* fix the backtest exception when volume is 0 or np.nan
* fix test_storage.py
* add backtest_daily
* modify backtest_daily's docstring
* add __repr__/__str__ to Position
* fix the bug of nested_decision_execution example
Co-authored-by: Young <afe.young@gmail.com>
Co-authored-by: you-n-g <you-n-g@users.noreply.github.com>