build: Enables FreeBSD support.

Changed hardcoded bash shebang to env to support multiple directory
structures (required to build on FreeBSD).

PR-URL: #238

build-template/build.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if test `uname` = Darwin; then
     cachedir=~/Library/Caches/KBuild

build.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if test `uname` = Darwin; then
     cachedir=~/Library/Caches/KBuild