add packaging scripts

packaging/ubuntu/postrm

@@ -0,0 +1,12 @@
+#!/bin/sh
+set -e
+
+if command -v systemctl >/dev/null 2>&1; then
+  systemctl daemon-reload
+fi
+
+if [ "$1" = "purge" ]; then
+  rm -rf /etc/bitoj
+fi
+
+exit 0