Update pipeline tag, link to paper

This PR ensures people can find the model at https://huggingface.co/papers/2310.20700.

README.md

@@ -1,4 +1,7 @@
 ---
-tags:
-- image-to-video
----
+pipeline_tag: image-to-video
+---
+
+## SEINE model
+
+This repository contains the SEINE model as presented in [SEINE: Short-to-Long Video Diffusion Model for Generative Transition and Prediction](https://huggingface.co/papers/2310.20700)