The ubuntu-minimal README states that the latest Ubuntu LTS
is the default, but currently that is not true. This patch
changes the default to the current LTS.
Change-Id: I10f28314d1a5969c20094194637cfe31219d228c
The ubuntu, and ubuntu-minimal elements both make use of a common set
of environment settings to determine the distribution name.
The ubuntu-minimal element also does a few extra things which would
appear to apply to both sets and bring in extra architecture support.
As such, these are included in the common element.
This intends to be part of a series of patches which will eventually
create a new element to build a minimal ubuntu-systemd-container
element which can be used for lxc/nspawn containers.
Change-Id: Ia4e620f7d3fa6215484a8d218cea2f28bd1ffaee
