change the layout to spread the menu across the nav bar depending on viewport

[satra]

if you see the following site: http://kaworu.github.io/octostrap3/

one a computer/tablet browser in wide mode, the menu expands out, while it compresses into the 3 lines icon on a smaller format display (like a phone). you can test it through the developer tools, or simply by expanding and compressing the size of the browser window.

it would be nice to have that capability on the nipy site. it seemed to be trivial till i realized the nipy site isn't using bootstrap.