[UI] Streamline workflow with "Paste from Clipboard"

[codedealer]

I am sure we're all tired from countless "Push x to y" buttons under every Gallery output, there are so many of them yet still not enough.

Proposal:

• Remove all the "Push..." buttons
• Each Gallery output gets "Copy to Clipboard"
• Each Image input gets "Paste from Clipboard"

This will declutter the UI and as a sweet bonus opens a (almost) seamless integration with your favorite tools! Paste directly from Photoshop/Krita/Google Images, move images from img2img to ESRGAN and back — all with to simple buttons.

Relevant context
Currently there is an open issue on Gradio gradio-app/gradio#735 to implement paste from clipboard but it's been open for half a year and seems pretty low on their priority list.
So, I figured we manage ourselves for the time being?
@altryne shameless tag since you're spearheading the UI overhaul currently

[altryne]

Saw this in the morning and had some time to mull this over.
Agree that the buttons are... getting out of hand.
From the other side, I really don't want to "simplify" the interface by adding 3 clicks for the same function folks use now.
Push changes the tab, and loads the image, without going through the users clipboard.

Paste from clipboard is a great suggestion! I absolutely think we can add this while we wait for Gradio.
And I cleaned up the button area a little bit in #421 , and .. we should somehow toe the balance of functionality and UI coherence.

Thanks for this, let's keep the discussion