avocado: Rename job output dir

We used 'run' as a prefix for avocado job output directories
after virt-test (basically, inertia). Let's use something
better:

job-[first 8 characters of job id]-timestamp

This way the job id starts to be more prominent in the
human interface as well.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado: Refer to 'debug log' as 'job log'

Instead of using 'debug log' we can use 'job log', as it
is a human readable log of the job execution.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
Set 'INTERRUPTED' status for interrupted tests

If we press Ctrl+C, the test that was being executed
still does not have a status, and that reflects in the
job log with a None printed in the final status.

So, if there's no status yet, we should safely (?)
assume that the test was interrupted.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado: Refer to test debug log as test log

It is more clear as to the purpose of the file.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>
avocado: Change job results dir from 'logs' to 'job-results'

Another change to clarify the purpose of each directory.

Signed-off-by: Lucas Meneghel Rodrigues <lmr@redhat.com>