
Provides two additional visual schemes for widgets

Fl:scheme(s)
where s is one of NULL, "plastic", "gtk+", or "none"

NULL doesn't actually change the scheme itself, but allows
the script to inherit a scheme from a user's environment. The
FLTK_SCHEME environment variable or the fltk.scheme X11 resource
can be set to one of the above three strings to allow scripts
that include Fl:scheme(NULL) to display your desired scheme.

Since this functionality isn't an automatic part of FLTK, an
alternative to adding the command to all your scripts could be
to run them with murgaLua -e 'Fl:scheme(NULL)' scriptname,
or in some systems can set this as an alias to murgaLua. I suppose
there are several ways for the end user to get the desired effect
without having to edit every script...
