Log Message:
Update xscreensaver to 4.18:
 4.18                              14-Aug-2004
   * Oops, pay no attention to the man behind the curtain.
 4.17                              14-Aug-2004
   * New hacks, anemotaxis and memscroller.
   * Fixed a bad bug that caused vidwhacker to never die.
   * Fixed normals and lighting in polyhedra.
   * Don't reuse the window when changing hacks (to work around bugs in some GL
     implementations.)
   * Made xscreensaver-getimage-file skip thumbnail-sized images.
   * Fixed endian problem in barcode on non-x86.
   * Updates to webcollage, apple2, fuzzyflakes, atunnel, and pacman.
   * Timing tweaks to bubble3d, bouncingcow, engine, gltext, lavalite,
     molecule, spotlight, sballs, boxed, blinkbox, and circuit.
   * Configure updates for Fedora core 2 / xorg 6.7.0.
   * Compile without warnings under gcc 3.3.3.
   * I give up: don't blank or lock the screen if we can't get a keyboard grab.
     In that case, both choices are bad.