[test] Fix devtools unittest_i18n when ran without pytest There is currently some weird error, requiring both to hack cubicweb.__path__ and to stop using load_module_from_name to load the registry. Introduce a dependency on to-be-released version of logilab common integrating fix for https://www.logilab.org/ticket/6085650 Do some extra import cleanups along the way.

usr/bin/cubicweb-ctl usr/bin/
usr/lib/python2*/*-packages/cubicweb/cwctl.py
../cubicweb-ctl.bash_completion etc/bash_completion.d/cubicweb-ctl