Specify urxvt for colors

Using a wildcard caused many Qt-based programs to have an awful dark
background.

Thanks to ecmel at [0] for the tip.

[0] https://bbs.archlinux.org/viewtopic.php?pid=1057062#p1057062
Remove scrolling wheel script

Added /usr/share/X11/xorg.conf.d/20-trackpoint.conf, which actually
works.
Highlight trailing whitespace