[Feature Request] Sticky ip for containers

[zentarim]

Description:
At now, we have abilities:

• Assign static IP to container
  or
• Assign dynamic IP to container
  But we not have ability:
• Allocate 'sticky' address from dynamic pool\subnet. i.e. dynamic address, tied to container until container removal.
  Something like

host SOMEHOST {
hardware ethernet 00:1F:6A:21:71:3F;
fixed-address 10.0.0.1;
}

in isc-dhcpd

Use case:
Docker uses in many test environments. Sometimes, you need to create dozens of container, tied with dozens of nets.
It is very convenient to do this topologies automatically with dynamic addresses.
But, due the test cases, some containers can be started\stopped in random order. Also several containers in one network can be stopped and runned in random order.
This implies changes of ip address in containers. And this is a key problem, because not all software can dynamically adjust their configs in this situation.
Creation of similar topologies with static config is tremendously painful, and described ability can help.

Proposal:
Add parameter --sticky for 'docker network connect' command (or allow empty --ip parameter).
It woud give ability to automatic assign static address to docker. This address will be considered as allocated to this container until container removal, even this container is stopped,

Thanks in advance!