Shading Windows
===============
Many window managers allow a window to be "shaded"; when in this
state only the title bar of the window is visible.
- Command: shade-window window
Arrange for only the title bar of WINDOW to be visible.
- Command: unshade-window window
If the window is shaded, restore it to it's original state.
- Command: toggle-window-shaded
Toggle the shaded state of the window.
The `shaded' property of a window is set to `t' when the window is
shaded. If a window is added with this property already set, then the
window will appear in its shaded state.