Colab: added the ability to download models from civitai

[uptotec]

its hard and time consuming to download models and putting them in the right directory in google colab so I added the ability to download checkpoints and LoRAs from civitai using model URL. the code uses civitai api to get model info and downloads it in the right directory.
please let me know if this change is acceptable and if any changes is required.

[mashb1t]

Civitai now requires token auth for automated downloads, see #2041 (comment)

[uptotec]

It works with me without issue. Please give it a try and tell me if any problem arise.

[mashb1t]

Thanks for the bump, seems like Civitai has removed the global restrictions for auth again... 🤷
Please check the grammar in the provided code, see suggestions.
The code works fine but i am sadly not authorized to merge this PR.

[uptotec]

made the required changes and added a check to make sure the downloaded model is SDXL.

[mashb1t]

While i understand the reasoning behind this code we still have to consider that SD1.5 models can be used as refiners. I'd propose to keep the code but please keep this in mind when reviewing.

[uptotec]

this code is for colab and colab has the refiner disabled by default.

[mashb1t]

@uptotec please check out #2423 and feel free to provide your feedback / learnings

[Chandima1990]

Hi is this going to be merged? @lllyasviel?