Spu

- [bugfix] Fix iota type mismatch.

20220425

- [Feature] Add tanh support.
- [bugfix] Fix secret shift wrong answer.

20220424

- [bugfix] Fix secret shift.

20220422

- [Feature] Add python simulation module.
- [Feature] Support general sort comparator.
- [Feature] Support remainder operation.
- [Feature] Support arithmetic right shift operation.
- [API] Change DataType definition, support more accurate encoding.

- [bugfix] Fixed several macOS build issues.

20220412

- [API] Add storage_type/data_type, remove type_data.
- [Experimental] Log(natural logarithm) is calculated with Pade approximation
instead of Householder's approximation.
- [API] Fix typo, goldschmdit.
- [Improvement] fxp div, improvement accuracy with normal distributed inputs.

20220325