reorganize debian packages (Closes: #1168)
- Merge cubicweb-core into cubicweb-common
- Fix lintian errors
- Install bash_completion file correctly
- Clean debian/rules
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