Tiled-mode for project_images.py and resumable training

[dimitry12]

This PR contains two improvements:

• new command-line argument for project_images.py: --no-tiled which allows to switch to factory-default projection into 1x512 dlatents-space (useful for evaluation of "semantic" quality of the model);
• a tweak in training loop to resume from the latest network-snapshot if one is found in the --result-dir

[rolux]

Yes this both makes sense. I'll try and add it to the next release. There are going to be a few major changes, mostly for video encoding.

[woctezuma]

Would you mind explaining the idea behind tiled mode? I found your PR while looking for information about this exact change. I suspect tiled mode leads to better projection results.

That could explain why I get different projection results with Nvidia's original project and this one.

[woctezuma]

Alright, I discovered this thread #2 and will read about it tomorrow. I think it might contain the answer.