use code blocks in readme

README.md

@@ -8,6 +8,7 @@ A simple tool to help make it easier to turn your tweet rants into real blog pos
 ### Usage
 Requires `TWITTER_CONSUMER_KEY` and `TWITTER_CONSUMER_SECRET`, both of which you can only get if you have a registered developer account and an application created for twitter.
 
+```
 Usage: twit2blog [opts]
 
 Options:
@@ -16,6 +17,7 @@ Requires `TWITTER_CONSUMER_KEY` and `TWITTER_CONSUMER_SECRET`, both of which you
 
 For more information read the Github readme:
   https://github.com/weskerfoot/Twit2Blog#readme
+```
 
 Example: `twit2blog -t:1234 -u:alice | pandoc --from=markdown --to=html > thread.html`