sockopt interface binding on Windows

Just came accross an article https://chaochaogege.com/2021/08/01/57/#windows-%E5%B9%B3%E5%8F%B0. It seems that IP_UNICAST_IF socket option can be used to set the outgoing interface for outbound packets under Windows. The implement can be refered from 
https://github.com/WireGuard/wireguard-go/blob/5846b622837e04dbc35b153d9ceda7fd66397520/conn/bind_windows.go#L567.
