bootmail encryption and shutdown messages now supported

I've made two pretty cool changes to the bootmail utility...

1. Bootmail now sends a message on both boot, and shutdown, using an upstart job.  Big thanks to Clint Byrum for a bit of help on that one!
2. Bootmail has always sent GPG-signed email.  But now, it will actually send GPG-encrypted email too!  All you need to do is set the RECIPIENT_KEYID variable in /etc/bootmail/gpg.conf to your GPG key id, and bootmail will send you GPG encrypted AND signed boot and shutdown messages!

Now, perhaps you wondering why, or how one would use this...

Actually, I have all of my EC2 instances set to install and use bootmail.  With this, I get an email when I start, reboot, and shutdown an instance.  I find it helps me remember what instances I have have running at any one time, by keeping the email in my Inbox (I practice Inbox Zero).

Moreover, I use cr-gpg with Gmail, so that I can read GPG encrypted email and verify GPG signatures within my Gmail web interface.  Check out this post for more information on how to set that up!

:-Dustin