ref: 15b2a406cc0e11377cee12b5a112c003f7250a7f
dir: purgatorio/libtk/radio.tk
radiobutton .u -text {Upper case} -variable case -value u radiobutton .l -text {Lower case} -variable case -value l radiobutton .i -text {Ignore case} -variable case -value i pack .u .l .i -anchor w -fill x