Custom model statuses with gradio.Info/Warning/Error

[NathanPruyne]

Currently the only feedback given during model processing is the MODEL.PROCESSING shown in the status box, but for longer processing times it might be good if we can give more continuous feedback. We could probably be able to accept gradio.Info statuses and display the contents of each in the status box during processing.

[xribene]

Good idea.
Maybe a related issue is this #294. I was thinking that there are some statuses that appear for a very brief moment and then overwriten by the next one. It could be usefull to somehow see all past statuses.

[xribene]

Also check if we can accept the gradio.Info that are invoked by HF.
Related to #291