+Changes since 2.16: Added a -window-id argument to most hacks, so that they
+ can draw on arbitrary externally-provided windows.
+ Synched with xlockmore 4.11a01.
+ Added `flow' hack.
+ Added `atlantis' GL hack.
+ Renamed `puzzle' hack to `jigsaw', since xlock already
+ had a different mode called `puzzle'.
+ Made it self-configure properly when Motif 2.1.0 is
+ being used (requires -lXp now, sigh...)
+Changes since 2.15: Made `flag' able to do XPM images.
+ New look for the xscreensaver logo (`xroger').
+ Fixed compilation error on Suns with adjunct passwords.
+ Got multi-architecture builds working again.
+ Some configure tweaks for building on HPUX and Solaris.
+ Fixed bug in decayscreen.
+ Fixed typo in passwd.c.
+ Made `cynosure' not die when colormap is full.
+Changes since 2.14: Added `cynosure' hack.
+ Added `moire2' hack.
+ Tweaked `erase.c' some more.
+ Made unfading a bit smoother.
+ Added `vidwhacker' hack (not installed by default.)
+ Added `stairs' hack.
+ Split `escher' into `cage' and `moebius', as per
+ xlockmore.
+ Changed subprocess handling to use sigaction() instead
+ of signal() if it's available (this is necessary for
+ SCO but should work fine on other systems too.)
+ Various other tweaks.