This is next part of networkd rewrite.
This implements three new resource types coupled with controllers which
process the default configuration, merges and applying changes.
TimeSync was set up to watch the time servers resource. This is a no-op
for now, but once DHCP is implemented, this would enable time server
configuration coming from DHCP.
Signed-off-by: Andrey Smirnov <smirnov.andrey@gmail.com>
