Lots of fixes related to EUCA-5179 and ebs functionality.

Fixes for DASManager reload() and changed lv naming. Also added explicity db clean on cleanup of export
Fixes for BfEBS instance start from stop. Was accidentally using root volume for request to SC instead of other attached volumes.

Fixed disconnect perl script for netapp/emc where rescan check was incorrect and rescan was happening when it should not

Changed lv/vg names from using random chars to labelled as the volume id

Added a bunch to make the Overlay/DAS detach synchronous and to implement separation of unexport and unexportAll.

Renamed attach/detach to export/unexport throughout SC since it is more accurate. Split LVM ops out into the
LVMWrapper class to clear up Overlay an DASManagers.

Added EucalyptusUnsupportedOperationException to handle the unexport() call in DAS/Overlay so that case can be
differentiated from other failures.

Changed some in VolumeInfo and VolumeToken to do better lookup of invalid and inactive exports.

Changed volume state update on CLC to not rever to GENERATING state if no actualDeviceNam valid is found or is invalid is found as that is now a legitimate state for an unattached volume

Removed AOE entities tweaks to volume tokens and added some tests

DescribeVolumes in SC return valid token instead of connection string now.

Added token tracking and cleanup as well as export tracking in the db.

Also made changes in the storage interfaces so changed the Overlay/DASManagers
to conform with those changes. Removed the list of iqns for attach/detach. Added
a detachFromAll() function to explicitly

VolumeInfo now has a reference to the set of VolumeTokens for it. Only one should
be marked valid at a time for any volume. Each VolumeToken has a set of
VolumeExportRecords to track the ip,iqn, and connection string for each export.
There may be multiple exports valid for a single token.