Improve the schema command with filtering option.
meta data and workflow data are hidden by default. show-meta and show-workflow
option are added to display them. Another "hide-type" option allow to hide
additional entities type.
"""Common subpackage of cubicweb : defines library functions used both on the
hg stserver side and on the client side
:organization: Logilab
:copyright: 2001-2010 LOGILAB S.A. (Paris, FRANCE), license is LGPL v2.
:contact: http://www.logilab.fr/ -- mailto:contact@logilab.fr
:license: GNU Lesser General Public License, v2.1 - http://www.gnu.org/licenses
"""