* Add Debian
Add work for Debian 9, 10, 11 - which are the only ones still under
maintenance at this time
* Remove Virtualbox ISO file after install
* Fix Ubuntu 18.04 virtualbox
Ubuntu 22.04 has the tools available and does not need to install from
ISO. This was hanging, though no output seemed to indicate why. So we're
avoiding the ISO altogether and going with the Ubuntu packages
Lots of other, small quality of life improvements to build process
Output of build serial console to artifacts upon failure
Reducing verbosity of Packer, now that serial output is captured
Fixed sizing problems with the boot partitions of Ubuntu versions
Use of Mac builders for Virtualbox targets
Updating Ubuntu builders to 22.04, as well
Greg Hellings