For the shell scripts, if you source this from a shell session it will set
and export COLORFGBG to 0;15 for dark backgrounds and 15;0
for light backgrounds which is a convention used by some programs.
Since I find this a little arcane, the program also sets and exports
LC_DARK_BG to 1 for dark backgrounds and 0 for light.
The LC_ (locale) assists in some ssh configurations which often will
let environment variables with that prefix get passed along and set
to a remote ssh session.
