This class wraps the comparison function in a way that is compatible with
std::map and std::set. This, too is generally useful, so it should be moved
to the generic header.
At the same time, the criterium for less-than is changed from "equal to -1"
to "smaller than 0", because technically the comparison function may return
other values.
This is due to the fact static strings flagged translated ( _("string") notation) are not translated when they are static only if they are not inside a dll.
When they are static inside a dll, the dictionary is already loaded, and the constructor translate them.
Therefore they can be translated twice in dialogs are calling wxGetTranslation to show them, if the application is run from kicad.
But if the application is run as stand alone, the translation is made only once (as expected).
Fix minor 3D viewer issues (includling change number of segments and its optimization to draw pad holes.)
Fix Bug #1439132 (track and via list on toolbar not always refresh after loading a board).
Remove useless tool in Modedit.