Instead of making msg.c an ifdef hell for unix vs. windows code, move
the code to separate functions defined in terminal-unix.c/terminal-
win.c.
Drop the code that selects random colors for --msgmodule prefixes.
This comes with a real change in behavior: now the signal handler is set
only when the terminal input code is active (e.g. not with
--no-consolecontrols), but this should be ok.
wm4