GitLab

* support custom sigmas and timesteps, dpm euler

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Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
Co-authored-by: Benjamin Bossan <BenjaminBossan@users.noreply.github.com>
Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>

* fix

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Co-authored-by: yiyixuxu <yixu310@gmail,com>
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* add fast tests for dpm-multi

* add more tests

* style

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Co-authored-by: yiyixuxu <yixu310@gmail,com>

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Co-authored-by: yiyixuxu <yixu310@gmail,com>
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* add use_karras_sigmas

* add karras test

* add doc

* Fix DPM single

* add test

* fix one more bug

* Apply suggestions from code review
Co-authored-by: StAlKeR7779 <stalkek7779@yandex.ru>

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Co-authored-by: StAlKeR7779 <stalkek7779@yandex.ru>

* fix multistep dpmsolver for cosine schedule (deepfloy-if)

* fix a typo

* Update src/diffusers/schedulers/scheduling_dpmsolver_multistep.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Update src/diffusers/schedulers/scheduling_dpmsolver_multistep.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Update src/diffusers/schedulers/scheduling_dpmsolver_multistep.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Update src/diffusers/schedulers/scheduling_dpmsolver_multistep.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* Update src/diffusers/schedulers/scheduling_dpmsolver_multistep.py
Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* update all dpmsolver (singlestep, multistep, dpm, dpm++) for cosine noise schedule

* add test, fix style

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Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>

* up

* correct some

* up

* finish