Fix exit code

Exit with proper exit code (1) and an error message if elasticsearch
executable binary does not exists or has insufficient permissions to
execute.

Squashed commit of the following:

commit 9768d316303418ba4f9c96d3f87c376048a1b1bc
Author: Puru <tuladharpuru@gmail.com>
Date:   Fri Apr 22 23:26:47 2016 +0545

    Fixed ES_HOME typo

commit 79a2b0394297f8b02b6f71b71ba35ff79f1a684e
Author: Puru <tuladharpuru@gmail.com>
Date:   Sun Apr 10 11:00:24 2016 +0545

    Improve elasticsearch startup script test

    Added improvement as per conversation in https://github.com/elastic/elasticsearch/pull/17082#issuecomment-206459613

commit 7be38e1fefd4baa6ccdbdc14745c00f6dc052e0c
Author: Puru <tuladharpuru@gmail.com>
Date:   Wed Mar 23 13:23:52 2016 +0545

    Add elasticsearch startup script test

    The test ensures that elasticsearch startup script exists and is executable.

commit d10eed5c08260fa9c158a4487bbb3103a8d867ed
Author: Puru <tuladharpuru@gmail.com>
Date:   Wed Mar 23 12:30:25 2016 +0545

    Fixed IF syntax and failure message

commit 6dc66f616545572485b4d43bee05a4cbbf1bed72
Author: Puru <tuladharpuru@gmail.com>
Date:   Sat Mar 12 11:08:11 2016 +0545

    Fix exit code

    Exit with proper exit code (1) and an error message if elasticsearch executable binary does not exists or has insufficient permissions to execute.

distribution/deb/src/main/packaging/init.d/elasticsearch

@@ -92,8 +92,10 @@ export ES_JAVA_OPTS
 export JAVA_HOME
 export ES_INCLUDE
 
-# Check DAEMON exists
-test -x $DAEMON || exit 0
+if [ ! -x "$DAEMON" ]; then
+	echo "The elasticsearch startup script does not exists or it is not executable, tried: $DAEMON"
+	exit 1
+fi
 
 checkJava() {
 	if [ -x "$JAVA_HOME/bin/java" ]; then

qa/vagrant/src/test/resources/packaging/scripts/70_sysv_initd.bats

@@ -57,6 +57,18 @@ setup() {
     install_package
 }
 
+@test "[INIT.D] elasticsearch fails if startup script is not executable" {
+    local INIT="/etc/init.d/elasticsearch"
+    local DAEMON="$ESHOME/bin/elasticsearch"
+    
+    sudo chmod -x "$DAEMON"
+    run "$INIT"
+    sudo chmod +x "$DAEMON"
+    
+    [ "$status" -eq 1 ]
+    [[ "$output" == *"The elasticsearch startup script does not exists or it is not executable, tried: $DAEMON"* ]]
+}
+
 @test "[INIT.D] daemon isn't enabled on restart" {
     # Rather than restart the VM which would be slow we check for the symlinks
     # that init.d uses to restart the application on startup.