Update README.md

Adding DNS-Swapper Project back after it was accidently removed

Signed-off-by: roots84 <stefan.bautz@gmail.com>

README.md

@@ -193,7 +193,7 @@ While quite outdated at this point, [this original blog post about Pi-hole](http
 - [Pi-hole metrics](https://github.com/nlamirault/pihole_exporter) exporter for [Prometheus](https://prometheus.io/)
 - [Magic Mirror with DNS Filtering](https://zonksec.com/blog/magic-mirror-dns-filtering/#dnssoftware)
 - [Pi-hole Droid: Android client](https://github.com/friimaind/pi-hole-droid)
-
+- [Windows DNS Swapper](https://github.com/roots84/DNS-Swapper), see [#1400](https://github.com/pi-hole/pi-hole/issues/1400)
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 ## Coverage