simplify viewer2d UX to just use "true" or unclassified states
simplify viewer2d UX to just use "true" or unclassified states

Users no longer care for the "false" classification state, and just
want to toggle between "true" and unclassified with fewer clicks...

informatics-isi-edu/synspy,informatics-isi-edu/synspy,informatics-isi-edu/synspy