Creating a RadioBox

radioBox opts initial

radioBox :: [(Picture,a)]
         -> Int 
         -> Component (Gauge (a,Int), DisplayHandle)

create a vertical list of exclusive RadioItems options. The initial value will be the option at index initial in opts (i.e., zero-indexed). If index is outside the perimeters of the option list, the boundary value that is closest is for the initial choice, i.e., an index of -1, is transformed into 0. If the list is empty, you lose. The handle returned by radioBox, a Gauge reports the current value and the index it is at in the option list. If you don't need the extra index, use mapGauge.