preserving default route with openvpn

[Casey Harkins <caseyharkins gmail com>]

When using NetworkManager-openvpn with the "Only use VPN connection for 
these addresses option, NetworkManager leaves me with no default route 
after the VPN connection is established. I would expect the default 
route to remain unchanged (same as before starting the VPN connection).

I've poked around the code a bit and followed things to 
nm_system_vpn_device_set_from_ip4_config(), but figured I'd post here 
before digging too deep into the code (in case its been addressed already).


-casey