[plt-scheme] DrScheme/OLPC sans Sugar

I am successfully running the vanilla Fedora 9 build of 4.1.2 on an XO-1 
running build 767 (the recent G1G1 refresh).

Memory is of course an issue.  I am not running DrScheme on top of 
Sugar, but rather the smaller XFCE wm.  I have disabled every tool other 
than Browser, Check Syntax, Graphical Debugger, Macro Stepper, and 
Version.  Even with these changes, the system would not host the full 
DrScheme debugger until I configured it with some swap space (by 
default, the XO-1 has no swap partition).  It now swaps to a file on a 
SD card: slow, and hard on the card, but effective.

The DrScheme interface was unusable, with giant menus and giant fonts 
and a Preferences dialog that stretched far off the bottom of the 
screen, until I configured XFCE to scale its fonts to 150 DPI.  I am not 
a savvy enough X user to hack in the /etc/X11 directory, and DrScheme 
was not using the window manager's font preferences.

The vanilla build requires GL, so I have Mesa installed, allowing MrEd 
to load.  However, the SGL samples appear to be dlopening the wrong 
library name (libGL.so instead of libGL.so.1).