Added font style declarations into the version stylesheet

I cannot test this change locally, but we want the "This documentation is for an older version of Riak" text to be styled as in the 1st example image, not the 2nd.

![right](https://f.cloud.github.com/assets/3535767/1943495/78ddc4d4-7fab-11e3-9cb5-e577b7f67d14.png)
![wrong](https://f.cloud.github.com/assets/3535767/1943496/78ebdc7c-7fab-11e3-975f-f0b746366b92.png)