Stop forwarding when removing vpn

src/freedombone-app-vpn

         rm -rf /etc/openvpn
     fi
     firewall_disable_vpn
+
+    echo 0 > /proc/sys/net/ipv4/ip_forward
+    sed -i 's|net.ipv4.ip_forward=.*|net.ipv4.ip_forward=0|g' /etc/sysctl.conf
+
     remove_completion_param install_vpn
 
     # remove any client keys