adapt to changes in libtriv

pub/src/axis.cpp

pub/src/commands.cpp

pub/src/curve.cpp

pub/src/dualplot.cpp

pub/src/edif.cpp

pub/src/expr.cpp

pub/src/file_in.cpp

pub/src/file_out.cpp

pub/src/manip.cpp

pub/src/rssm.cpp

pub/src/var.cpp

test/t1.inp

test/t3.inp

test/t4.inp