Add WSL doc

wsl/README.md

@@ -0,0 +1,34 @@
+## Force DNS Usage inside VPN
+
+```bash
+$ cat /etc/systemd/system/vpn-dns.service
+[Unit]
+Description=VPN DNS Configuration
+
+[Service]
+Type=oneshot
+ExecStart=/bin/vpn-dns.sh
+Environment=TERM=xterm
+
+[Install]
+WantedBy=multi-user.target
+```
+
+```bash
+$ cat /bin/vpn-dns.sh
+#!/bin/bash
+
+echo "Getting current DNS servers, this takes a couple of seconds"
+
+/mnt/c/Windows/System32/WindowsPowerShell/v1.0/powershell.exe -Command '
+$ErrorActionPreference="SilentlyContinue"
+Get-NetAdapter -InterfaceDescription "WireGuard Tunnel*" | Get-DnsClientServerAddress | Select -ExpandProperty ServerAddresses
+Get-NetAdapter | ?{-not ($_.InterfaceDescription -like "WireGuard Tunnel*") } | Get-DnsClientServerAddress | Select -ExpandProperty ServerAddresses
+' | \
+        awk 'BEGIN { print "# Generated by vpn fix func on", strftime("%c"); print } { print "nameserver", $1 }' | \
+        tr -d '\r' > /etc/resolv.conf
+clear
+```
+### Show Networks
+
+c/> Get-NetAdapter