Add multistep DPM-Solver discrete scheduler (#1132)
* add dpmsolver discrete pytorch scheduler
* fix some typos in dpm-solver pytorch
* add dpm-solver pytorch in stable-diffusion pipeline
* add jax/flax version dpm-solver
* change code style
* change code style
* add docs
* add `add_noise` method for dpmsolver
* add pytorch unit test for dpmsolver
* add dummy object for pytorch dpmsolver
* Update src/diffusers/schedulers/scheduling_dpmsolver_discrete.py
Co-authored-by: Suraj Patil <surajp815@gmail.com>
* Update tests/test_config.py
Co-authored-by: Suraj Patil <surajp815@gmail.com>
* Update tests/test_config.py
Co-authored-by: Suraj Patil <surajp815@gmail.com>
* resolve the code comments
* rename the file
* change class name
* fix code style
* add auto docs for dpmsolver multistep
* add more explanations for the stabilizing trick (for steps < 15)
* delete the dummy file
* change the API name of predict_epsilon, algorithm_type and solver_type
* add compatible lists
Co-authored-by: Suraj Patil <surajp815@gmail.com>
