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.

"""pre 3.6 bw compat"""
# pylint: disable-msg=W0614,W0401
from warnings import warn
warn('moved to cubicweb.mail', DeprecationWarning, stacklevel=2)
from cubicweb.mail import *