This command will create a 'close' button in the message window for the invoking
character. If no window is currently on screen, it will be created. See 'close'.
There is one important difference, though - even though the message box will
have closed, the script execution will not stop, and commands after 'close2'
will still run, meaning an 'end' has to be used to stop the script, unless you
make it stop in some other manner.