code duplication in iscsi helper(s)

[John Griffith]

Our iscsi code, particularly the LVMISCSIDriver has become a bit.... ugly. There's also been some overlap in target helper code between items in driver.py, drivers/lvm.py, iscsi.py and finally brick/iscsi/iscsi.py.

The overlap and the spread of the methods between all of the classes (and an ugly inheritance model) make the code extremely difficult to follow and maintain. Juno seems like a good time to clean this all up and make it sane as well as more easily extendable.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/104701

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/105923

[OpenStack Infra (hudson-openstack)]

Change abandoned by John Griffith (<email address hidden>) on branch: master
Review: https://review.openstack.org/104701
Reason: Set this up as a POC and illustration, served it's purpose and is superseded.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/110534

[OpenStack Infra (hudson-openstack)]

Change abandoned by John Griffith (<email address hidden>) on branch: master
Review: https://review.openstack.org/105923

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/105923
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=d10fb796f491152486e394481e920479bab9e3d1
Submitter: Jenkins
Branch: master

commit d10fb796f491152486e394481e920479bab9e3d1
Author: John Griffith <email address hidden>
Date: Thu Jul 10 00:00:31 2014 +0000

    Add iSCSI Target objects as independent objects

    This patch is a step in decoupling the target
    methods and the Volume Driver's Control methods.

    This adds the targets directory and the new target objects
    that we use with the exception of IET (follow up for that later).
    TgtAdm and LIO drivers have been tested with the new LVM object.

    All existing drivers are still able to be specified and use the
    same objects and code-path they were using previously. New
    connector objects are only used when specifying the new driver.

    Next step will be mapping current ref LVM driver to the new
    LVM object and target model and working on the unit-tests.

    After that mark the "old" methods and objects as deprecated
    and we can then begin working on some other improvements.

    Partial-Bug: #1329139

    Change-Id: Iaa55e31e3dadc7dcb58112302c3807a8f92bcada

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/125239

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/131860

[OpenStack Infra (hudson-openstack)]

Change abandoned by Mike Perez (<email address hidden>) on branch: master
Review: https://review.openstack.org/110534

[OpenStack Infra (hudson-openstack)]

Change abandoned by Mike Perez (<email address hidden>) on branch: master
Review: https://review.openstack.org/125239

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/131860
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=c505cb8046a2d49a327838d32126c41852f2f8da
Submitter: Jenkins
Branch: master

commit c505cb8046a2d49a327838d32126c41852f2f8da
Author: John Griffith <email address hidden>
Date: Wed Oct 29 13:34:54 2014 -0600

    Add iSCSI Target objects as independent objects

    This patch is a step in decoupling the target
    methods and the Volume Driver's Control methods.

    This adds the targets directory and the new target objects
    that we use with the exception of IET (follow up for that later).
    TgtAdm and LIO drivers have been tested with the new LVM object.

    All existing drivers are still able to be specified and use the
    same objects and code-path they were using previously. New
    connector objects are only used when specifying the new driver.

    Next step will be mapping current ref LVM driver to the new
    LVM object and target model and continued work on the unit-tests.

    After that mark the "old" methods and objects as deprecated
    and we can then begin working on some other improvements.

    Change-Id: If02db137f936dc5b509fc81ca3c29ae4f87f1cb2
    Partial-Bug: #1329139

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/158829
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=8bb865a0aaaaf4ad9dd4e9848a818fe446a11752
Submitter: Jenkins
Branch: master

commit 8bb865a0aaaaf4ad9dd4e9848a818fe446a11752
Author: Mitsuhiro Tanino <email address hidden>
Date: Wed Feb 25 19:16:39 2015 -0500

    Implement IET target driver

    When introducing Change-Id: I43190d1dac33748fe55fa00f260f32ab209be656,
    IET driver was not implemented. This patch adds IET target for new
    iscsi target driver model.

    Certification results:
        https://bugs.launchpad.net/cinder/+bug/1428758

    Closes-Bug: #1409918
    Closes-Bug: #1329139

    Co-Authored-By: Anish Bhatt <email address hidden>
    Change-Id: I165a592bb3a39728fcc3d8ee4162b579c13ba928