Update readme for visualization

Author: HugoLaurencon

ac_dc/visualization/README.md

@@ -1,5 +1,9 @@
 # Visualization tool
 
+Use this visualization tool online at https://huggingface.co/spaces/huggingface/text-data-filtering.
+
+However, it is faster (and can handle in practice up to three times more documents) by running the code on your computer.
+
 1) Use get_data_for_visualization.py to get the json gathering examples with their computed statistics for the language you chose.
 It uses the streaming mode of the Datasets library, so no need to download the dataset, but you have to download the fasttext model (for the language identification) and the kenlm / sentencepiece models (for the perplexity).