Add pipeline tag, enable download stats

This PR ensures downloads work for your model, and makes sure it can be found at https://huggingface.co/models?pipeline_tag=depth-estimation&sort=trending

README.md

@@ -1,5 +1,7 @@
 ---
+pipeline_tag: depth-estimation
 license: mit
+library_name: diffusion-single-file
 ---
 
 # CleanDIFT Model Card