CSS tidyup, JS error fix

I better formatted the CSS within `geo-kit.css`, as well as added the `background-color` property to the class `icon-button`. 

FF was rendering the buttons in a way which didn't display the SVG icons when there was no default background colour set. I didn't look into that, but hey, problem solved. So now the background colour for the buttons is white.

As for the JS error, I moved the `$mapSelect`, and `$mapButton` variable declarations to the top where the rest of the declarations are. This got rid of JS not being able to find the `$mapSelect` variable.