Update sample configuration to dump logs on failure
Update sample configuration to dump logs on failure

qinwf/r-travis,hadley/r-travis,craigcitro/r-travis,robzhu/r-travis,robzhu/r-travis,qinwf/r-travis,eddelbuettel/r-travis,craigcitro/r-travis,eddelbuettel/r-travis,hadley/r-travis