Creates a checkbox widget with name,
located at row and column with the text color of fcolor and background
color of bcolor. ccode is an optional ascii code of the check mark that
will be printed. The default check mark character is ascii code 251 (a
The tcheck widget has the form: [X] Caption, where X is the check
name: The name of the tcheck widget.
row: The line on which tcheck will be printed.
col: The column of the left-most side of the tcheck widget.
fcolor: The color that is used to print the text.
bcolor: The color that is used to print the background.
caption: The tcheck caption.
ccode: An optional ascii code of the character to print for check mark.