add listmonk update script

updates/listmonk.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+set -e
+export XDG_RUNTIME_DIR=/run/user/$UID
+
+release=`curl -L https://api.github.com/repos/knadh/listmonk/releases/latest -s | jq -r '.tag_name'`
+# listmonks file identifier is lacking the 'v'
+release=${release//v}
+installdir=$HOME/bin
+
+echo ">>> Listmonk is currently running: $($installdir/listmonk --version)"
+echo "======== Latest release is [ $release ] ========"
+read -p "=> Reply yY to proceed..." -n 1 -r
+echo
+if [[ ! $REPLY =~ ^[Yy]$ ]]
+then
+    [[ "$0" = "$BASH_SOURCE" ]] && exit 1 || return 1
+fi
+
+systemctl stop --user listmonk
+
+curl -sL https://github.com/knadh/listmonk/releases/download/v$release/listmonk_${release}_linux_amd64.tar.gz | tar xvz -C $installdir/
+$installdir/listmonk --upgrade
+
+systemctl start --user listmonk
+
+sleep 2
+systemctl status --no-pager --user listmonk