DefaultNetworkBridge is now `zdocker0`

By default, services likes to bind to the ip address specified by the first NIC found, which is typically sorted by name, with the first one usually called `eth0`.
Unfortunately, `docker0` ends up before `eth0`, and thus, services will bind to the private IP specified by `docker0`.
A sysadmin would then need to configure the service to explicitly bind to the correct IP address (and we all know that most sysadmins can't be bothered...).
This patch makes the default docker bridge interface name `zdocker0`, which should basically sort last in the list of network interface names.