use env to select sh

vpnsetup.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env sh
 #
 # Script for automatic setup of an IPsec/L2TP VPN server on Ubuntu LTS and Debian 8.
 # Works on dedicated servers and any KVM- or Xen-based Virtual Private Server (VPS).

vpnsetup_centos.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env sh
 #
 # Script for automatic setup of an IPsec/L2TP VPN server on 64-bit CentOS/RHEL 6 & 7.
 # Works on dedicated servers and any KVM- or Xen-based Virtual Private Server (VPS).

vpnupgrade_Libreswan.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env sh
 #
 # Script to upgrade Libreswan on Ubuntu and Debian
 #

vpnupgrade_Libreswan_centos.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/usr/bin/env sh
 #
 # Script to upgrade Libreswan on CentOS and RHEL
 #