Add option to choose partition alignment mode

[OpenStack Infra]

https://review.openstack.org/312933
Dear bug triager. This bug was created since a commit was marked with DOCIMPACT.

commit af247ea07a469c467b83687013a68b0e3cff05fe
Author: Alexander Gordeev <email address hidden>
Date: Thu May 5 15:52:40 2016 +0300

    Add option to choose partition alignment mode

    Under certain circumstances due to that alignment, the end of
    particular partition could cross 1M boundary. And due to actual
    partition' bounderies being rounded up, fuel-agent mistakenly
    assumes that partition couldn't fit within provided boundaries
    and raises errors.WrongPartitionSchemeError.

    However, some h/w data storages are well known for reporting
    relatively huge optimal IO sizes (16M or even bigger), so the 1M
    room can't be enough. Thus, optimal aligning is not an option.
    In such cases, it's better to proceed with minimal mode.

    It's the minimum aligment needed to align the partition properly
    to physical blocks which avoids performance degradation.

    Partial-Bug: #1543233
    DocImpact

    Change-Id: I1dd94731f497f3deb47cec9a23957e3706c2fb3b

[Alexander Adamov (aadamov)]

The resolved issue has been already reported in MOS 9.0 release notes https://docs.mirantis.com/openstack/fuel/fuel-9.0/release-notes.html#resolved-issues. Closing

[Alexander Adamov (aadamov)]

Ignore previous comment. Added to MOS release notes 9.1 https://review.fuel-infra.org/#/c/25024/

[Andrey Lavrentyev (alavrentyev)]

Verified on 9.1 snapshot #299

UBUNTU_MIRROR_ID=ubuntu-2016-09-14-213640
CENTOS_MIRROR_ID=centos-7.2.1511-2016-05-31-083834
MOS_UBUNTU_MIRROR_ID=9.0-2016-09-22-142322
MOS_CENTOS_OS_MIRROR_ID=os-2016-06-23-135731
MOS_CENTOS_PROPOSED_MIRROR_ID=proposed-2016-09-22-152322
MOS_CENTOS_UPDATES_MIRROR_ID=updates-2016-06-23-135916
MOS_CENTOS_HOLDBACK_MIRROR_ID=holdback-2016-06-23-140047
MOS_CENTOS_HOTFIX_MIRROR_ID=hotfix-2016-09-16-084322
MOS_CENTOS_SECURITY_MIRROR_ID=security-2016-06-23-140002