Add a "random" sorting option for home page

[rubinsandwich]

Under the "Home" tab in Theme Options, it would be extremely useful to have an additional option under each section (after "post count") where the user was given a "sort" option (date or random).

A lot of us (as seen in the forums) use some of these sections to pull up older (random) posts to highlight on the home page. This seems like a logical and easy way to let the user have control over it.