This is quite useful for userspace applications that can't cope with the
restriction, but it's still useful to impose other non-configurable
restrictions by using jails.
This happens in two ways:
1. LibCore now has two new methods for creating Jails and attaching
processes to a Jail.
2. We introduce 3 new utilities - lsjails, jail-create and jails-attach,
which list jails, create jails and attach processes to a Jail,
respectively.