[pkg] various debian packaging fixes - stop using *.install.in files, just use wildcards in *.install - switch to X-Python-Version (preferred for dh_python2) - also call dh_python2 for /usr/share/cubicweb, not just public modules - drop long obsolete ginco and erudi migration code from cubicweb-ctl.postinst - fix cubicweb-ctl cleanup: purge code belongs in postrm, not prerm - don't compress changelog.html

../../doc/book usr/share/doc/cubicweb-documentation
../../doc/_build/html usr/share/doc/cubicweb-documentation
../../debian/cubicweb-doc usr/share/doc-base/cubicweb-doc