The `snap --prepare-image` command will currently look into the
gadget and create a /etc/cloud/cloud.cfg configuration if the
gadget contains a "cloud.conf" file in cloud-init format. But
even if there is no such file an empty /etc/cloud directory is
created.
This empty directory ends up on /writable/system-data/etc/cloud
and that will block the initial boot from populating that dir
with the data from the core18 /etc/cloud directory when this
dir is in "transition" mode in the /etc/system-image/writable-paths.
Once that is done we need to also support ds-identify.conf or
switch to a cloud.conf/ directory instead of the current file
only approach. The reason is that we do not want to merge the
cloud config from core18 and from the gadget as this is messy.
Instead it should either come from the gadget or from the core18.
travis: short circuit failures in static and unit tests travis job (#6299)
* travis: short cicruit failures in static and unit tests task
It's super annoying to have the Travis job execute all scripts, while the first
one has failed. This makes it hard to find out the failure that occurred in
--static checks as it doesn't really stand out and it followed by a couple of
pages of unit tests log.
