Use the new socket command to reload zuul-launcher

It no longer accepts SIGHUP.

Change-Id: I672a945be3c9ae628a8069af6a7519b7b2e32bda

files/zuul-launcher.init

@@ -82,13 +82,7 @@ do_stop()
 # Function that sends a SIGHUP to the daemon/service
 #
 do_reload() {
-    #
-    # If the daemon can reload its configuration without
-    # restarting (for example, when it is sent a SIGHUP),
-    # then implement that here.
-    #
-    start-stop-daemon \
-        --stop --signal 1 --quiet --pidfile $PIDFILE --name zuul-launcher
+    $DAEMON reconfigure
     return 0
 }
 

templates/zuul.conf.erb

@@ -63,6 +63,7 @@ default_to=<%= @smtp_default_to %>
 log_config=/etc/zuul/launcher-logging.conf
 jenkins_jobs=<%= @jenkins_jobs %>
 workspace_root=<%= @workspace_root %>
+socket=/var/lib/zuul/launcher.socket
 <% if @worker_private_key_file != "" -%>
 private_key_file=<%= @worker_private_key_file %>
 <% end -%>