This fix tries to fix the issue raised in 29044 where
the IPAM options is missing in swarm network mode
after the service is deployed. Before the service
is deployed, the IPAM options is available.
The reason for the issue is that, before service is
deployed, `network inspect` is querying the swarm and
obtained the correct information.
However, after service is deployed, swarm executor
does not pass the IPAM options to the backend (daemon).
Also after service is deployed, `network inspect` is
actually querying the local daemon for information.
At this time the network information with missing IPAM
options is returned.
This fix fixes the issue by updating the swarm network
allocator and swarm executor.
A separate PR for swarmkit will be opened.
An integration test has been added to cover the change.
This fix fixes 29044.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>