Fix home page on mobile devies.

Previously, the home page was wider than mobiles, on devices with a
width of less than 435px. This specifically targets them with CSS
directives, which makes the fonts / the logo smaller. This works well on
an iPhone 4, but has not been tested on devices with smaller width.

This was aided by changing the main container to a `container-fluid', as
well as all the rows to `row-fluid'.