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.
from os.path import join
from cubicweb.toolsutils import create_dir
option_renamed('pyro-application-id', 'pyro-instance-id')
create_dir(join(config.appdatahome, 'backup'))