Creates a menu item which has two states, on or off, represented by
a check mark with a text label specified by label.
If label is NULL or not specified then no label is
created. If label contains underscore characters then the character
following the underscore will be underlined and the character following
the first underscore will be used as the mnemonic keyboard accelerator.
The use_underline parameter defaults to
TRUE. If use_underline is set to
FALSE the label text will not be parsed
for mnemonic characters.