Delphi.py failure prints to STDOUT

[graik]

The Delphi wrapper writes to STDERR or STDOUT when execution fails. This obstructs testing:

exe.reduce.Test.test_reduce  .................................. ok
exe.delphi.Test.test_delphi  .................................. Delphi failed. Please check the program output in the field `output` of this Delphi instance (e.g. `print x.output`)!

The last message from DelPhi reads as follows:
 .........  PROGRAM EXITS SUCCESSFULLY : WITH TOTAL 221 WARNING(S) ........


ERROR
exe.delphi.Test.test_delphiCharges2  .......................... ok

Remove print() statements or adjust verbosity.