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 https://github.com/lllyasviel/Fooocus/issues/2041#issuecomment-1911319750

[uptotec]

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

[uptotec]

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

[uptotec]

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

[mashb1t]

@uptotec please check out https://github.com/lllyasviel/Fooocus/pull/2423 and feel free to provide your feedback / learnings