Stable WarpFusion v0.5.17-nightly - scheduling (Patreon)

Hey there! 

Time to add some scheduling options to the pipeline. 

I've began with replacing skip steps and frames_skip_steps with more widespread strength setting and its respective schedule, so that newcomers will be able grasp the concept more easily. 

The schedules are available for flow_blend and skip_steps / frames_skip_steps for now. Turbo skip steps work the old way, need to think how to universally implement scheduling for those, too.

style_strength_schedule: controls the skip steps setting. 1 means 0% (no) skip steps, 0 means 100% skip steps, 0.3 means 70% skip steps,  etc.

schedule is a python list, so you can do all the usual stuff like this: [0.5]*3+[0.2] to use 0.5 strength / 50% skip steps for the first 3 frames and the use 0.2 strength / 80% skip steps for the rest of the frames.

A simple list like [0.5, 0.2] mimics the legacy behavior with 50% skip_steps and 80% frames_skip_steps.

flow_blend_schedule works in a similar way, but mind that it start blending frames at frame 1, so the flow_blend_schedule = [0.5,0.1] will skip 0.5 and use 0.1 for the blend between the 1st and the 2nd frames.

I will be adding more schedules to get rid of all those "first frame / all other frames" settings, as those may be confusing.

upd: move flow_blend_schedule defaults back to 0.999

upd: add steps, init_scale, init_latent_scale schedules. Scheduling steps is useful with strength scheduling, when you end up with low strength and thus very few diffusion steps. For example, 0.2 strength at 50 total steps = 10 diffusion steps, which may be too little with animated prompts. Setting steps higher for frames with low strength lets us have more steps without losing coherence.