Fixed the link I created earlier.

README.md

@@ -59,7 +59,7 @@ digd.js --input <path/to/dns.json>
 digd.js --input ./samples/db.json
 ```
 
-(For more information on the JSON structure see [JSON Database File](#JSON_DATABASE_FILE) 
+(For more information on the JSON structure see [JSON Database File](#json-database-file) 
 below.)
 
 ### Testing