If daemon is not installed, exit 5

According to documentation[1] we should use exit code 5 if program is
not installed. This also fixes a bug with our default PREFIX for
ubuntu.

[1] http://refspecs.linuxbase.org/LSB_3.1.1/LSB-Core-generic/LSB-Core-generic/iniscrptact.html

Change-Id: I5166cf4970a67cce7af3d2e88d5809e9814a8946
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

files/etc/default/zuul-launcher

@@ -4,4 +4,4 @@
 
 # The prefix used when zuul-launcher was installed. Be sure to update this value
 # if you are using a virtualenv.
-PREFIX=/usr
+PREFIX=/usr/local

files/etc/default/zuul-merger

@@ -4,4 +4,4 @@
 
 # The prefix used when zuul-merger was installed. Be sure to update this value
 # if you are using a virtualenv.
-PREFIX=/usr
+PREFIX=/usr/local

files/etc/default/zuul-server

@@ -4,4 +4,4 @@
 
 # The prefix used when zuul-server was installed. Be sure to update this value
 # if you are using a virtualenv.
-PREFIX=/usr
+PREFIX=/usr/local

files/etc/init.d/zuul-launcher

@@ -25,7 +25,7 @@ USER=zuul
 DAEMON=$PREFIX/bin/zuul-launcher
 
 # Exit if the package is not installed
-[ -x "$DAEMON" ] || exit 0
+[ -x "$DAEMON" ] || exit 5
 
 # Load the VERBOSE setting and other rcS variables
 . /lib/init/vars.sh

files/etc/init.d/zuul-merger

@@ -25,7 +25,7 @@ USER=zuul
 DAEMON=$PREFIX/bin/zuul-merger
 
 # Exit if the package is not installed
-[ -x "$DAEMON" ] || exit 0
+[ -x "$DAEMON" ] || exit 5
 
 # Load the VERBOSE setting and other rcS variables
 . /lib/init/vars.sh

files/etc/init.d/zuul-server

@@ -23,7 +23,7 @@ USER=zuul
 DAEMON=$PREFIX/bin/zuul-server
 
 # Exit if the package is not installed
-[ -x "$DAEMON" ] || exit 0
+[ -x "$DAEMON" ] || exit 5
 
 # Load the VERBOSE setting and other rcS variables
 . /lib/init/vars.sh