Build system: Add missing set -e

So that shell scripts do not blunder on after errors.

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>

build

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/sh -e
 
 # build
 #	Simple wiringPi build and install script

examples/blink.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/sh -e
 #
 # blink.sh:
 #	Standard "blink" program in wiringPi. Blinks an LED connected

examples/q2w/blink.sh

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/sh -e
 #
 # blink.sh:
 #	Standard "blink" program in wiringPi. Blinks an LED connected

gpio/newVersion

@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/sh -e
 #
 # newVersion:
 #	Utility to create the version.h include file for the gpio command.