TODO: document -blr units, and possibly fix blur (20 seems to be about 3 pixels,
80 seems to be about 3 pixels, too, just much slower).
TODO: when window partially off-screen, -blr does not have any effect anymore.
-TODO: rid of global dpy variable.
TODO: borderLess resource might not work on some systems - might be another
gentoo phantom bug or a real problem, such as using it too early.
8.