In preview_handler, preset request.extra_path so a preview of a template relying on it won't explode.
In preview_handler, preset request.extra_path so a preview of a template relying on it won't explode.

We really need a sensible way to deal with the three slightly different page handlers (preview, base, application)...
mjl/feincms,matthiask/feincms2-content,joshuajonah/feincms,michaelkuty/feincms,feincms/feincms,matthiask/feincms2-content,matthiask/django-content-editor,hgrimelid/feincms,matthiask/django-content-editor,joshuajonah/feincms,pjdelport/feincms,nickburlett/feincms,pjdelport/feincms,matthiask/feincms2-content,feincms/feincms,pjdelport/feincms,michaelkuty/feincms,hgrimelid/feincms,mjl/feincms,nickburlett/feincms,joshuajonah/feincms,hgrimelid/feincms,joshuajonah/feincms,matthiask/django-content-editor,michaelkuty/feincms,matthiask/django-content-editor,mjl/feincms,nickburlett/feincms,nickburlett/feincms,michaelkuty/feincms,feincms/feincms