Navigation elements should collapse to <select> elements on small widths

[ajpiano]

Both of our primary navigation elements look cluttered and are inefficient on a small width device/browser

We should generate these elements as s for use at small widths.

[kleinmaetschke]

On this tonight.

[ajpiano]

Great, thanks @kleinmaetschke

[kleinmaetschke]

@ajpiano I'm nearing the finish line (branch link) on this. I want to style it a bit more, but I've got the base Chosen.js in there and running. Although using the "Header: Browse" bit from tinynav seems to create a navigation item in Chosen. So, I've removed that for now. Chosen is supposed to support using data-placeholder="Placeholder", but adding that via jQuery doesn't seem to do the trick. Any ideas?