Merged debian init script changes from elastic#16718.

Fixes elastic#69

templates/init/debian/elasticsearch.j2

@@ -177,7 +177,7 @@ case "$1" in
 		i=0
 		timeout=10
 		# Wait for the process to be properly started before exiting
-		until { cat "$PID_FILE" | xargs kill -0; } >/dev/null 2>&1
+		until { kill -0 `cat "$PID_FILE"`; } >/dev/null 2>&1
 		do
 			sleep 1
 			i=$(($i + 1))