This command will displays a box on the screen for the invoking character, if no
such box is displayed already, and will print the string specified into that
box. There is normally no 'close' or 'next' button on this box, unless you
create one with 'close' or 'next', and while it's open the player can't do much
else, so it's important to create a button later. If the string is empty, it
will show up as an empty line.

mes "Text that will appear in the box";

Inside the string you may put color codes, which will alter the color of the
text printed after them. The color codes are all '^<R><G><B>' and contain three
hexadecimal numbers representing colors as if they were HTML colors - ^FF0000 is
bright red, ^00FF00 is bright green, ^0000FF is bright blue, ^000000 is black.
^FF00FF is a pure magenta, but it's also a color that is considered transparent
whenever the client is drawing windows on screen, so printing text in that color
will have kind of a weird effect. Once you've set a text's color to something,
you have to set it back to black unless you want all the rest of the text be in
that color:

mes "This is ^FF0000 red ^000000 and this is ^00FF00 green, ^000000 so.";

Notice that the text coloring is handled purely by the client. If you use non-
english characters, the color codes might get screwed if they stick to letters
with no intervening space. Separating them with spaces from the letters on
either side solves the problem.