Update EMC SMI-S iSCSI Driver

Refactor EMC SMI-S based iSCSI driver.  There are lots of common code
that can be shared between iSCSI and FC drivers using SMI-S.  Break
the original emc.py into two files: emc_smis_common.py and
emc_smis_iscsi.py.  Also added support for get_volume_stats() and
create_cloned_volume().  get_volume_stats() will be revisited after
winston-d's changes.  copy volume<->image will be revisited after
avishay-il's changes.

Change-Id: I90dc3599ec2fd5bb86a3e988111a8aee5de7efea
Get updated vol status in volume.api.reserve.

A race condtion was discovered where a nova volume attach
could easily be performed twice for the same volume.  Although
the cinder attach update would fail, this occured after the BDM
updates were made and in essence the attach to the compute instance
had already been issued.

This change simply forces a get from the DB of the volume-ref in the
reserve call and checks if an attach is already in progress.

Fixes bug: 1096983

Change-Id: Ie0e4156d691ee92b6981078ef0ba62f8c4cdf0c8
Fix hosts extension and enable its tests

This patch corrects the import in hosts.py, fix the DB API
service_get_by_host_and_topic raises ServiceNotFound exception with
right parameter and move tests to the right place so that they are
enabled.

Fix LP bug: #1104231

Change-Id: I07c486f456196a3812eb5274b950ab9560a51cf3
Merge "Get updated vol status in volume.api.reserve."
Merge "Update EMC SMI-S iSCSI Driver"
Merge "Fix hosts extension and enable its tests"
First Hacks to print out parameters

Change-Id: I2345f6bb355aa285eee0455380c580e4724f004e
Print out auth token, and log image_href

Change-Id: I1602bfe6c5aa7a4c6f1d5d25f175eb1362afb0eb
Use glance.get_api_servers to get glance parameters

Change-Id: I4e32b03f1ce43b3058e59c6a2ba093252438bb6b
Log out sr and vdi uuids

Change-Id: I6420f9a609e58ad221a94ad9860a46202aba48ec
Add debug messages

Change-Id: I16f4d30661ce417e8560f6868b351451a431af58
Update local volume reference

Change-Id: I1104b52b28359ac9a896344b0125bdd4f91432f9
uuid stack creation

Change-Id: I0a063be2c64debc85e0e5900958539e648a19557
Added uuid import

Change-Id: Ibfe0844792745da78668aa63bebbcef86c406304
Log out clone_image calls

Change-Id: Iebaa80c408efe3f226f13c1fd9bf4934ba91a0fd
uuid_stack will only contain the desired vhd

Change-Id: I2648c57d968e157b81c4ecb30d0ce75d9ed36319
Ask xenapi plugin to copy image

Change-Id: I7fd556ff0149dab786ea289bf66cbbc0f8b4de0c
Typo fix

Change-Id: I98a092a84c71576509af35db377b94aef54f1654
use finally, and do not use request to call the plugin

Change-Id: Ief29f75c75d0730d72f13d1dad3dd84ffca40ea2
Fix hack

Change-Id: I9b91da0d249989cbb80f25cdbc8d29c1a7acfcef