[Xmonad] darcs patch: add "Square" layout.

[Donald Bruce Stewart]

droundy:
> Mon Jun 11 19:10:48 PDT 2007  David Roundy <droundy at darcs.net>
>   * add "Square" layout.
>   This is probably only ever useful in combination with Combo.
>   It sticks one window in a square region, and makes the rest
>   of the windows live with what's left (in a full-screen sense).

Applied.

Could people contributing new layouts submit also a paragraph on what it
does, along with a screenshot suitable for inclusion on
xmonad.org/contrib.html?

Thanks!

-- Don