Added some colours for Ruby

# Before:
![screen shot 2014-01-20 at 20 53 14](https://f.cloud.github.com/assets/178448/1957661/95b95cb8-820c-11e3-9559-46f222605c18.png)

![screen shot 2014-01-20 at 20 54 20](https://f.cloud.github.com/assets/178448/1957674/bd20b562-820c-11e3-94e9-b7bb64875f7e.png)

# After:
![screen shot 2014-01-20 at 20 52 22](https://f.cloud.github.com/assets/178448/1957663/98d6d7e0-820c-11e3-9c95-0bb610fd4fde.png)

![screen shot 2014-01-20 at 20 54 41](https://f.cloud.github.com/assets/178448/1957675/c186e7d4-820c-11e3-98f2-55331a21c436.png)