Largely replace the Debian packaging with a new and much more up-to-date

Debhelper based version.

debian/dnsmasq-base.postrm

@@ -2,10 +2,9 @@
 set -e
 
 if [ purge = "$1" ]; then
-   if [ -x "$(command -v deluser)" ]; then
-     deluser --quiet --system dnsmasq > /dev/null || true
-  else
-     echo >&2 "not removing dnsmasq system account because deluser command was not found"
-  fi
+  userdel dnsmasq
   rm -rf /run/dnsmasq
 fi
+
+#DEBHELPER#
+