Upstart and release notes

[Bruno Wolff III]

Please include a warning in the release notes that if you have customized
inittab, you might need to do something to have those customizations
still apply after switching to upstart.
In my case I had the following line:
SV:123456:respawn:/command/svscanboot
And that wasn't being run in upstart.
I also need to check that this doesn't break nut which puts in commands
to shutdown on powerfail (and abort on restoration).
I also ignore ctrl alt del and that will probably need to be recustomized
as well.