Added script to generate systemd service file

It is needed for automatic server startup on test machines and VMs
used in automated tests.

install-systemd-service.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+DIR="$(cd -P "$(dirname "${BASH_SOURCE[0]}")" > /dev/null && pwd)"
+if [ ! -z "$1" ]
+then
+    CMD="httpperfserv $1"
+else
+    CMD=httpperfserv
+fi
+
+sudo sh -c "cat > /lib/systemd/system/httpperfserv.service <<EOF
+[Unit]
+Description=Benchmark http server
+After=network.target nss-lookup.target
+Documentation=https://github.com/vsukhoml/httpperfserv
+
+[Service]
+Type=simple
+ExecStart=${DIR}/${CMD}
+
+[Install]
+WantedBy=multi-user.target
+EOF"
+
+sudo systemctl daemon-reload
+sudo systemctl enable httpperfserv.service
+sudo systemctl start httpperfserv.service