Handle optgroup argument directly in create_content_type
Handle optgroup argument directly in create_content_type

Several initialize_type methods could not handle the additional argument.

matthiask/feincms2-content,nickburlett/feincms,matthiask/django-content-editor,hgrimelid/feincms,matthiask/feincms2-content,pjdelport/feincms,hgrimelid/feincms,michaelkuty/feincms,joshuajonah/feincms,joshuajonah/feincms,matthiask/django-content-editor,michaelkuty/feincms,feincms/feincms,matthiask/feincms2-content,mjl/feincms,mjl/feincms,matthiask/django-content-editor,hgrimelid/feincms,michaelkuty/feincms,joshuajonah/feincms,mjl/feincms,michaelkuty/feincms,pjdelport/feincms,nickburlett/feincms,nickburlett/feincms,feincms/feincms,joshuajonah/feincms,feincms/feincms,matthiask/django-content-editor,nickburlett/feincms,pjdelport/feincms