Port for Mac use

[jason-costello]

Make the following bits work on Mac (if even possible) ... I am researching comparable commands.

sig-716i/core/ifaces.go

Line 49 in 3147510

func (w *Wireless) downNetworkManager() *InternalError {

sig-716i/core/ifaces.go

Line 61 in 3147510

func (w *Wireless) upNetworkManager() *InternalError {

sig-716i/core/ifaces.go

Line 96 in 3147510

for idx, iface := range ifaces {

sig-716i/core/ifaces.go

Line 140 in 3147510

_, err := ExecCommand("ip", "link", "set", iface, "down")

sig-716i/core/ifaces.go

Line 147 in 3147510

_, err = ExecCommand("iwconfig", iface, "mode", mode)

sig-716i/core/ifaces.go

Line 154 in 3147510

_, err = ExecCommand("ip", "link", "set", iface, "up")