right into Persistent here.

__roles__ rather than a PermissionRoles.

validate.

Also fixed bug in handling proxy roles.

then aq_acquire needed to be called on it, but that wasn't hapenning.

Fixed appendCookie which didnt work.
Fixed expireCookie to use Expires in addition to Max-Age to make
it work for NS & IE, and added the ability to specify a path when
calling expireCookie which is required by NS Navigator to expire
a cookie that provided a path when it was set.