Minor to cms_date_format modifier

git-svn-id: http://svn.cmsmadesimple.org/svn/cmsmadesimple@9211 3d254a34-79dc-0310-9e5f-be208747d8a0
Swapping to is_frontend_request()

git-svn-id: http://svn.cmsmadesimple.org/svn/cmsmadesimple@9212 3d254a34-79dc-0310-9e5f-be208747d8a0