README formatting

README.md

@@ -84,7 +84,7 @@ iex(10)> ExW3.Contract.call(SimpleStorage, :get)
 
 Elixir doesn't have event listeners like say JS. However, we can simulate that behavior with message passing. The way ExW3 handles event filters, is that it starts a background process that will call eth_getFilterChanges every cycle. Whenever a change is detected it will send a message to the listener.
 
-```
+```elixir
 # Start the background listener
 ExW3.EventListener.start_link