Add exception handling for copy_volume_to_image()

The method require_driver_initialized occurs exception so that the
method volume_get will be not executed, and the variable 'volume'
will be not defined. In the "finally" code segment, the
volume['instance_uuid'] will get the UnboundLocalError, this patch
gets volume before require_driver_initialized to avoid the above
problem.

Change-Id: Ic8167383eb67c5016c9853da274455e0f202dc4d
Closes-Bug: #1322958
NetApp fix eseries concurrent vol map failure

This fixes the issue while mapping volume to host
when the requests are very close in time proximity.
The map operation has been synchronized.

Change-Id: I2e120d84d3b96faa4ab8d4324e70a089bcddeaa5
Closes-bug: #1312685
Fix a message format error in migration cleanup

In some situations, the volume migration failed. After the cleanup
begin, code was trying to format a string value as an int,
this caused "copy_error = True" not being invoked, resulted
in UnboundLocalError exception.

Change-Id: I445394cc06fe221804901e8014d60e870f0fe2f7
Closes-Bug: #1290317
Merge "Fix a message format error in migration cleanup"
Merge "Add exception handling for copy_volume_to_image()"
Merge "NetApp fix eseries concurrent vol map failure"