Add caddy example file. (#268)

* Added service example file

* Update system-md-example.service

* a

* Rename to `kitsune.service`, move to `contrib/` directory, make instructions comments instead

* Caddy example

* quick extra comments at the top of the file

* Add spaces in front of text comments, remove mention of Cloudflare (not relevant here), rename to "Caddyfile"

---------

Co-authored-by: aumetra <aumetra@cryptolab.net>

contrib/Caddyfile

@@ -0,0 +1,12 @@
+# Example file for Caddy
+# This should go in /etc/caddy/Caddyfile
+
+example.domain {
+    reverse_proxy 127.0.0.1:port # Should be port 5000 by default
+}
+
+# Example if you need to use specific certificates.
+#example.domain {
+#    tls /pathtofile/file.pem /pathtofile/file.key
+#    reverse_proxy 127.0.0.1:port
+#}