This patch improves init's dynamic reconfigurability with respect to
adjustments of the RAM quota assigned to the children.
If the RAM quota is decreased, init withdraws as much quota from the
child's RAM session as possible. If the child's RAM session does not
have enough available quota, a resource-yield request is issued to
the child. Cooparative children may respond to such a request by
releasing memory.
If the RAM quota is increased, the child's RAM session is upgraded.
If the configuration exceeds init's available RAM, init re-attempts
the upgrade whenever new slack memory becomes available (e.g., by
disappearing other children).