add .service file and update README a little.

README.md

@@ -42,6 +42,7 @@ jjakkekeyserver% exit
 ```
 
 #### postgres
+Probably not needed info, but postgres here is version 15.
 ```
 % sudo apt install postgresql postgresql-server-dev-xx
 % sudo -u postgres psql                                 # test if 'active' so to speak.

jjakkekeyserver.service

@@ -0,0 +1,18 @@
+[Unit]
+Description=jjakke's keyserver
+After=network.target
+
+[Service]
+Type=simple
+User=jjakkekeyserver
+Group=jjakkekeyserver
+WorkingDirectory=/var/jjakkekeyserver/keyserver
+ExecStart=/var/jjakkekeyserver/perl5/perlbrew/perls/perl-5.40.0/bin/hypnotoad -f /var/jjakkekeyserver/keyserver/keyserver
+Environment=PERL5LIB=/var/jjakkekeyserver/perl5/lib/perl5
+Environment=PATH=/var/jjakkekeyserver/perl5/perlbrew/bin:/var/jjakkekeyserver/perl5/perlbrew/perls/perl-5.40.0/bin:$PATH
+Restart=always
+RestartSec=5
+LimitNOFILE=4096
+
+[Install]
+WantedBy=multi-user.target