[testlib] put postgres test database in test/data/database directory with other (sqlite) test databases. Closes #9240765 Simplify .hgignore in passing.

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