Changes

OBS: gerrit_binpkgs: print verbose output

Print all shell commands and their output executed by build_srcpkgs.py
and build_binpkgs.py, instead of only printing them on error. This is
useful to see the output of the scripts downloading dependencies when
building sourcepackages.

Change-Id: Ie1dbde603351b1d26b66f3834b645b1f1f5bbfc8