feat(windscribe): static ip permanent port forwarding instructions (#122)

Author: ZeWaka

setup/providers/windscribe.md

@@ -66,9 +66,16 @@ services:
 
 ### VPN server port forwarding
 
+#### Ephemeral port forwarding
+
 1. Follow the [Windscribe instructions](https://windscribe.com/support/article/37/what-is-ephemeral-port-forwarding-and-how-to-use-it)
 1. In your container configuration, set `FIREWALL_VPN_INPUT_PORTS` to the port you have been assigned, for example: `FIREWALL_VPN_INPUT_PORTS=8099`
 
+#### Permanent port forwarding (static IP)
+
+1. Follow the [custom provider setup instructions](https://github.com/qdm12/gluetun-wiki/blob/main/setup/providers/custom.md), using the [openvpn](https://windscribe.com/getconfig/openvpn) or [wireguard](https://windscribe.com/getconfig/wireguard) configuration file that Windscribe provides for static ips.
+1. In your container configuration, set `FIREWALL_VPN_INPUT_PORTS` to the port you have been assigned, for example: `FIREWALL_VPN_INPUT_PORTS=8099`
+
 ## Servers
 
 To see a list of servers available, [list the VPN servers with Gluetun](../servers.md#list-of-vpn-servers).