Add install script

docs/guides/timelimit-server-setup.md

@@ -0,0 +1,27 @@
+# Server Setup
+
+There is a shell script for doing a mostly automated installation at <https://codeberg.org/timelimit/timelimit-server/raw/branch/master/docs/guides/timelimit-server-setup.sh>. During a test, it took 10 minutes to do a installation with it.
+
+**Read the messages which the script shows** - it is recommend to run it on a clean Debian 10 installation because it overwrites some configuration files.
+
+## Usage
+
+- download it (using wget or a webbrowser)
+- make it executable (``chmod +x timelimit-server-setup.sh``)
+- run it (``sudo ./timelimit-server-setup.sh``)
+- answer the questions
+
+## Requirements
+
+- a **public** IP address **with** a domain name
+- a reachable port 80 and 443 (which can need a port forwarding at your router)
+- a Debian 10 installation (or something comparable) which does not contain anything (important)
+- a mail address for sending automated mails (using SMTP) which should **not** be your primary mail address
+
+## Created setup
+
+- timelimit-server (as a systemd service)
+- postgresql (connected to timelimit-server using a unix socket)
+- nginx (connected to timelimit-server using a unix socket)
+- certbot (to get valid certificates)
+- a few helper commands with the ``timelimit-`` prefix