Comment 7 for bug 1435603

Reviewed: https://review.openstack.org/279436
Committed: https://git.openstack.org/cgit/openstack/fuel-astute/commit/?id=d09d2bfba97ca9359df1227dcdc8836e38bddfb1
Submitter: Jenkins
Branch: master

commit d09d2bfba97ca9359df1227dcdc8836e38bddfb1
Author: Dmitry Guryanov <email address hidden>
Date: Thu Feb 11 20:38:39 2016 +0300

    fix error reporting from shell and sync hooks

    1. Report exit codes from nodes, where command execution
       failed. I've changed return value of function
       run_shell_command. Now it returns nil in case of
       success and string descrition in case of error.
    2. Show different message for each exception handled
       in shell_hook.
    3. Fix warning about number of retires.

    I also think that it's better to increase timeout in
    nailgun, so timeout will be greater than retries * interval,
    in this case if command failed all times, the error will be
    'Failed to run command', not about timeout.

    Change-Id: I5051a84c9c146999ae7b3ef430ec3013989f1271
    Closes-Bug: #1435603