Jenkins is acting again - scoring patch when test was not run

[Nir Soffer]

Hi infra,

Jenkins gave my patch -1 because it Jenkins was broken:
http://jenkins.ovirt.org/job/vdsm_master_pep8_gerrit/7364/console

This is a major error; Jenkins should -1 a patch only if the it could run the
relevant test, and the test failed.

In this case the relevant test is running the pep8 tool, and scoring the patch
is correct if the tool returned with non-zero exit code.

Any other failure is CI error and should not effect the patch score.

If you can, it would be nice if jenkins would add a comment on gerrit, telling 
about errors. In this case, the status should be ERROR instead of FAILURE.

Examples:

When jenkins fails to run a test:
- http://jenkins.ovirt.org/job/vdsm_master_pep8_gerrit/xxxx/ : ERROR

When tests was run and failed:
- http://jenkins.ovirt.org/job/vdsm_unit_tests_gerrit_el/xxxx/ : FAILURE

When test was run and succeeded:
- http://jenkins.ovirt.org/job/vdsm_unit_tests_gerrit/xxxx/ : SUCCESS

Thanks,
Nir