t / t4101 / diff.2-3on commit travis-ci: use 'set -x' in 'ci/*' scripts for extra tracing output (4f26366)
   1--- a/frotz
   2+++ b/frotz
   3@@ -1,2 +1,3 @@
   4 a
   5+c
   6 b
   7\ No newline at end of file