add install script and instructions

install.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+truncate -s0 /etc/motd           # empty native static motd
+mkdir -p /etc/update-motd.d/     # create dedicated directory following ubuntu
+cp motd /etc/update-motd.d/      # copy the static motd banner into it
+chmod -x /etc/update-motd.d/*    # disable any existing script
+cp scripts/* /etc/update-motd.d/ # enable claranet motd
+
+echo "For distributions which does not use update-motd (e.g. ubuntu/debian), do not forget to add the following to /etc/pam.d/sshd:"
+echo "session    optional   pam_exec.so          stdout /etc/update-motd.d/00-basic"