The userRoutes and serverRoutes VPN properties are passed to connman via
dbus in the following form.

Variant array [struct {array [
    dict entry(
        string "ProtocolFamily"
        variant int32 4
    )
    dict entry(
        string "Network"
        variant string "172.18.13.1"
    )
    dict entry(
        string "Netmask"
        variant string "255.255.255.255"
    )
    dict entry(
        string "Gateway"
        variant string "172.18.13.5"
    )
]}]

These need to be converted to and from the appropriate datatypes used in
QML and javascript. This change adds the conversion functions needed for
this.