a suggestion to improve relabel_bse()
% ltlfilt --relabel-bool=pnn -f '(a & b & c) U (c & d & e)'
(p0 & p1) U (p1 & p2)
% ltlfilt --relabel-bool=pnn -f '(a & b & c) U (!c & d & e)'
(p0 & p1) U (!p1 & p2 & p3)
it would be nice if the second command could output (p0 & p1) U (!p1 & p2)
.