* Metadata cleanup - Maintain metadata within UI
This commit, when combined with Gradio 3.2.1b1+, maintains image
metadata as an image is passed throughout the UI. For example,
if you generate an image, send it to Image Lab, upscale it, fix faces,
and then drag the resulting image back in to Image Lab, it will still
remember the image generation parameters.
When the image is saved, the metadata will be stripped from it if
save-metadata is not enabled. If the image is saved by *dragging*
out of the UI on to the filesystem it may maintain its metadata.
Note: I have ran into UI responsiveness issues with upgrading Gradio.
Seems there may be some Gradio queue management issues. *Without* the
gradio update this commit will maintain current functionality, but
will not keep meetadata when dragging an image between UI components.
* Move ImageMetadata into its own file
Cleans up webui, enables webui_streamlit et al to use it as well.
* Fix typo
