PeRFlow: Piecewise Rectified Flow as Universal Plug-and-Play Accelerator

### Model/Pipeline/Scheduler description

A competitor of LCM-Lora, with higher generation quality and consistency regardless number of steps

Project page: https://piecewise-rectified-flow.github.io/
Github: https://github.com/magic-research/piecewise-rectified-flow/tree/main

### Open source status

- [X] The model implementation is available.
- [X] The model weights are available (Only relevant if addition is not a scheduler).

### Provide useful links for the implementation

Maybe we can add the new scheduler to Diffusers