changed some topic page widths so the gutter fills the availible space...

...also right-aligning user-dropdown

![screenshot 2014-03-03 01 16 05](https://f.cloud.github.com/assets/1681963/2306904/b2ce3580-a29b-11e3-825b-7777805295d0.png)

![screenshot 2014-03-03 01 16 17](https://f.cloud.github.com/assets/1681963/2306905/b4c060fc-a29b-11e3-92a5-f458ec7b2a53.png)