New macro that will change the radii of all circles in the current selection set that have the specified radius to a new radius.
There is no undo button but the New Radius value and the Old Radius value are swapped so clicking Set Radii a second time should undo the last change only.
This was thrown together rather quickly, so please let me know if you have any problems. The code is open if anyone would like to poke around and clean it up.
