Update library name

As it looks like the checkpoints are compatible with Transformers/PEFT, this PR updates the library name, and also add the relevant pipeline tag (similar to Idefics).

README.md

@@ -2,7 +2,8 @@
 license: other
 license_name: sample-code-license
 license_link: LICENSE
-library_name: viper-vpe
+library_name: peft
+pipeline_tag: image-text-to-text
 ---
 
 # ViPer: Visual Personalization of Generative Models via Individual Preference Learning