Add training datasets to metadata

Fixes #3 by updating the README with the training dataset Hub ids.

README.md

@@ -8,6 +8,11 @@ language:
 - en
 pipeline_tag: text-to-speech
 inference: false
+datasets:
+  - parler-tts/mls_eng_10k
+  - blabble-io/libritts_r
+  - parler-tts/libritts_r_tags_tagged_10k_generated
+  - parler-tts/mls-eng-10k-tags_tagged_10k_generated
 ---
 
 <img src="https://huggingface.co/datasets/parler-tts/images/resolve/main/thumbnail.png" alt="Parler Logo" width="800" style="margin-left:'auto' margin-right:'auto' display:'block'"/>