Use /usr/bin/env in shebangs

Stop assuming that bash is in /bin, and that perl and python are in
/usr/bin, etc.
Instead, use env command to find these commands in the path.

tools/hitag2crack/crack2/runtest.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if [ "$1" == "" ]; then
 echo "runtest.sh testfile"