The stable 2.0 version from January does not, I added this last month (May 30th). So you need a recent snapshot version, and it will be in the next stable release.
Currently the iconsets and icons displayed by the icon picker you see on the widget configuration pages is indeed hardcoded. You have more flexibility in custom widgets and templates though. See for instance here.
KNF-UF icons can’t be bundled with HABPanel because of their “ShareAlike” licensing.