Add language tag

Hi
A PR to improve the referencing of your dataset 🤗

README.md

@@ -1,19 +1,22 @@
+---
+language:
+- ar
+- bg
+- de
+- el
+- es
+- fr
+- hi
+- ru
+- sw
+- th
+- tr
+- ur
+- vi
+- zh
+---
 XNLI consists of 10k English sentences translated into 14 languages: 
 
-ar: Arabic
-bg: Bulgarian
-de: German
-el: Greek
-es: Spanish
-fr: French
-hi: Hindi
-ru: Russian
-sw: Swahili
-th: Thai
-tr: Turkish
-ur: Urdu
-vi: Vietnamese
-zh: Chinese (Simplified)
 
 The XNLI 15-way parallel corpus can be used for Machine Translation as evaluation sets, in particular for low-resource languages such as Swahili or Urdu.
 
@@ -35,4 +38,4 @@ Please consider citing the following paper if using this dataset:
   year =    "2018",
   publisher =   "Association for Computational Linguistics",
   location =    "Brussels, Belgium",
-}
+}