The major change for Ubuntu is to mark many of these as optional, like
with Debian and the old guides. As I move away from zsys, this will end
up being more like the old way.
This was also discussed in #306 and #307, but this change has
trade-offs. It can reduce the number of datasets created on the
system, but it does so by increasing the complexity to read and follow
the guide.
Then I just harmonized Debian with Ubuntu. Aside from whitespace,
reordering, rewording, the substantive changes were to drop /opt and
add /var/lib/NetworkManager.
Signed-off-by: Richard Laager <rlaager@wiktel.com>
