Get ubuntu 16.04 on ppc to work!

Created by: doublej472

This is actually ubuntu 16.04.02 (now 16.04.03), but it should be very similar for our purposes.

This whole PR is basically a conglomeration of chef bento and our old packer repos, with fixes thrown everywhere to pass the openstack taster tests. So far it passes the security tests fine, but it has trouble mounting some filesystems from the volumes, which is why this is still a work in progress.

I'm making this PR early if anyone wants to look at what I've done to get ubuntu to cooperate (This took a lot of random changes to get working), and if anyone wants to use the images they are listed as Ubuntu 16.04 LE doublejtest and Ubuntu 16.04 BE doublejtest on openpower-controller.osuosl.org

This is still in desperate need of squashing, I'll get to it once volumes work completely.