added banners for location with color

@ltw. Here's a screenshot of our progress with Pairing is Caring. http://i.imgur.com/ZYABghQ.png?1

We implemented background colors and "enbiggenated" the font for mentor availability locations. Now hopefully people won't schedule sessions for cities they don't live in. Yaaaaay.
`<br>`s have no place in semantic markup. You should be using margin, padding or line-height to control layout.