insert-close-paren in color:text<%>

• (send a-color:text insert-close-paren position char flash? fixup?) -> void
     position : natural-number?
     char : char?
     flash? : boolean
     fixup? : boolean

  Position is the place to put the parenthesis and char is the parenthesis to be added. If fixup? is true, the right kind of closing parenthesis will be chosen from the pairs list kept last passed to start-colorer, otherwise char will be inserted, even if it is not the right kind. If flash? is true the matching open parenthesis will be flashed.