Fix ohmyz.sh link

Change http://ohmyz.sh link to use proper markdown syntax

README.markdown

@@ -5,7 +5,7 @@ Oh My Zsh is an open source, community-driven framework for managing your [zsh](
 
 __Oh My Zsh is a way of life!__ Once installed, your terminal prompt will become the talk of the town _or your money back!_ Each time you interact with your command prompt, you'll be able take advantage of the hundreds of bundled plugins and pretty themes. Strangers will come up to you in cafés and ask you, _"that is amazing. are you some sort of genius?"_ Finally, you'll begin to get the sort of attention that you always felt that you deserved. ...or maybe you'll just use the time that you saved to start flossing more often.
 
-To learn more, visit http://ohmyz.sh and/or follow [ohmyzsh](https://twitter.com/ohmyzsh) on Twitter.
+To learn more, visit [ohmyz.sh](http://ohmyz.sh) and/or follow [ohmyzsh](https://twitter.com/ohmyzsh) on Twitter.
 
 ## Getting Started