Allow integrating a different font easily

[kghbln]

It will be great to switch the skin to use another default font with a dedicated configuration parameter, e.g., $wgChameleonFontFiles, which sets the font files' location and automatically applies them to everything in the wiki—at least something like this.

Someone needs to clone the font files to some location on the server and add a lot of CSS voodoo to the "Mediawiki:Chameleon.css" page. I am unsure if this is the easiest approach and if this can be improved on the Chameleon side.