prettify data fields section

README.md

@@ -66,14 +66,14 @@ Extractive-QA
 
 <pre>
 {
-  `id`: str
-  `title`: str
-  `context`: str
-  `question`: str
-  `answers`: {
-    `answer_start`: [int]
-    `text`: [str]
-	}
+  id: str
+  title: str
+  context: str
+  question: str
+  answers: {
+    answer_start: [int]
+    text: [str]
+  }
 }
 </pre>