Add README

README.md

+DynDNS frontend plugin for sfphoton modular web server
+======================================================
+
+This is a DynDNS frontend and reverse proxy for my personal website. Features:
+
+- Register and update DynDNS records
+- Authentication and authorization
+
+This frontend uses my [DynDNS implementation](https://git.sch.bme.hu/schulczf/dyndns-server) as a backend. It is only secure if this runs on localhost or is only available through a secure link.
+
+Usage
+-----
+
+Just install this under sfphoton modular web server as any plugin. Add permissions `dyndns` to website users.
+
+Dependencies
+------------
+
+My [DynDNS implementation](https://git.sch.bme.hu/schulczf/dyndns-server).
+
+Required config
+---------------
+
+```json
+{
+		"DYNDNS_SERVER_URL": "http://127.0.0.1:3002",
+}
+```
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