[devtools] vreg becomes a class ppty After multiple devtools refactoring, the vreg used for test is now *always* got from the repository. Making this explicit is a step toward simplification of the vreg handling during various initialisation phases. Related to #2944813

debian/tmp/usr/bin/cubicweb-ctl usr/bin/
debian/tmp/usr/lib/PY_VERSION/site-packages/cubicweb/cwctl.py usr/lib/PY_VERSION/site-packages/cubicweb
debian/cubicweb-ctl.bash_completion etc/bash_completion.d/cubicweb-ctl