Update README.md

Small Mixture of Experts (MoE) trained on pure language modelling task (WikiText-103, document level). This MoE was presented in [this paper](https://aclanthology.org/2023.findings-emnlp.49/).

README.md

@@ -1,3 +1,9 @@
 ---
 license: apache-2.0
----
+datasets:
+- EleutherAI/wikitext_document_level
+language:
+- en
+metrics:
+- perplexity
+---