Less restrictive from_pretrained function

[lludlow]

I noticed some models did not have the proper file names and would fail to download.

This will allow a broader range of models to be used

[xhoxye]

Is it possible to make it use the downloaded safetensors model？

[lludlow]

closing as https://github.com/lllyasviel/Omost/pull/27 handles this better