Font changes and a 'Who are we?' section in about.

I changed the fonts to Segoe UI Light, the font we shall now use on all
webpages. I added a temporary 'Who are we?' section that I shall be
upgrading with some styling later on. If you don't want you Scratch
username on there, feel free to take it off. I just thought you should
get some credit for your amazing styling/CSS skills. :)