Fix the status indication in the client service. The status of the
management server and the signal server was incorrect if the network
connection was broken. Basically the status update was not used by
the management and signal library.
The peer login expiration ACL check introduced in #714
filters out peers that are expired and agents receive a network map
without that expired peers.
However, the agents should see those peers in status "Disconnected".
This PR extends the Agent <-> Management protocol
by introducing a new field OfflinePeers
that contain expired peers. Agents keep track of those and display
then just in the Status response.
The ConnStatus is a custom type based on iota
like an enum. The problem was nowhere used to the
benefits of this implementation. All ConnStatus
instances has been compared with strings. I
suppose the reason to do it to avoid a circle
dependency. In this commit the separated status
package has been moved to peer package.
Remove unused, exported functions from engine
