Otherwise it's not possible to write tests reliably because sync messages may be executed multiple
times if they arrive from different transports. This should fix flaky
`test_transport_synchronization`.
Also always emit `TransportsModified` if the primary transport is changed by a sync message, even if
it doesn't contain `SyncData::Transports`.
Also don't decrease `add_timestamp` in `save_transport()` if nothing else changes, this doesn't make
sense.
Fix get_secondary_addrs() which was using
`secondary_addrs` config that is not updated anymore.
Instead of using `secondary_addrs` config,
use the `transports` table which contains all the addresses.
`login_param` module is now for user-visible entered login parameters,
while the `transport` module contains structures for internal
representation of connection candidate list
created during transport configuration.
