Introducing Modular Diffusers - Composable Building Blocks for Diffusion Pipelines

Modular Diffusers introduces a flexible method for building diffusion pipelines by composing reusable blocks, complementing the existing `DiffusionPipeline` class. This approach allows users to mix and match components to create custom workflows tailored to specific needs. The system facilitates the creation of custom blocks, such as one for depth estimation, which can then be inserted into existing pipelines like a ControlNet workflow. This modularity simplifies complex pipeline construction and is demonstrated with code examples for running inference, creating custom blocks, and managing model components for memory efficiency.