fix apt provider retries logging to warning with a final error

[Matthew Mosesohn]

Detailed bug description:
 QA reports APT failures when there is only 1 APT retry, but it's not obvious from the error logs that it was successful and proceeded.
Steps to reproduce:
 N/A
Expected results:
 N/A
Actual result:
 N/A
Reproducibility:
 N/A
Workaround:
 N/A
Impact:
 N/A
Description of the environment:
 Operation system: <put your information here>
 Versions of components: <put your information here>
 Reference architecture: <put your information here>
 Network model: <put your information here>
 Related projects installed: <put your information here>
Additional information:
 <put your information here>

Example failure.
https://product-ci.infra.mirantis.net/job/9.0.system_test.ubuntu.thread_7/69/artifact/logs/fail_error_deploy_controllers_from_custom_nodegroup-fuel-snapshot-2016-04-05_23-53-36.tar.xz.filtered.log

We should use WARN status logging for output of each failure, then if we fail MAX_TRIES, report as ERR status.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/302716

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/302716
Committed: https://git.openstack.org/cgit/openstack/fuel-library/commit/?id=b481d50509816134cc1aac7f512b0799f1a72f0b
Submitter: Jenkins
Branch: master

commit b481d50509816134cc1aac7f512b0799f1a72f0b
Author: Kyrylo Galanov <email address hidden>
Date: Thu Apr 7 14:11:13 2016 +0200

    Make apt_fuel logging more obvious

    Existing output was often mistaken for an error.
    Fix with pushing warning instead of error messages when retries are not
    run out of.

    Change-Id: I0e7ed2c591297f44e6690d8c3a73625b151ad3cf
    Closes-bug: #1567339

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/mitaka
Review: https://review.openstack.org/304374

[OpenStack Infra (hudson-openstack)]

Change abandoned by Kyrylo Galanov (<email address hidden>) on branch: stable/mitaka
Review: https://review.openstack.org/304374