Most of these are display hacks because (at least on OSX) assigning
bitmaps or doing a layout before the controls are visible tends to
not work. There are also some layout cleanups and some layout hacks
(horizontal radio button groups, for instance, lay out on top of each
other on OSX).
Fixes https://gitlab.com/kicad/code/kicad/issues/7491
When calculating E series resistors, display error percentage down to
0.01% but rather than showing 0.00% error for smaller values, we now
show the error is "<0.01%" until it is exact.
Fixes https://gitlab.com/kicad/code/kicad/issues/5731