LVM: Activate source snap LV when cloning from volume

Similar to the change made in:
01a2199 LVM: Activate source LV before cloning from it

Previous change only fixed this issue for clone-from-snapshot.

This activates the source snapshot LV when cloning from volume
as well, fixing the problem where cloning fails due to inability
to open the source LV device.

Change-Id: If48be8516fd71738cb83a91683c33d02f227b9d6
Related-Bug: 1252423
Closes-Bug: 1260786
Extra_spec containing '/' can't be deleted

This patch validates the keys of the extra specs
before setting them.
This will make possible to remove those keys.
It allows alphanumeric characters, underscores,
periods, colons and hyphens.

Change-Id: Ic2e5d7ce42c8ecb7ee45cd168bd008035fd4bbdf
Closes-Bug: #1259711
Add create_iscsi_target stub to TargetAdmin

This should be defined in TargetAdmin, as it is assumed to be
present in all subclasses by callers.

IetAdm and LioAdm may need additional work to behave as desired
in all circumstances (such as volume extend), but this should
at least stabilize things in the meantime.

Closes-Bug: 1273480

Change-Id: Iac1381286ea07982e6db7f7c7abf3f9100e4be50
Merge "Extra_spec containing '/' can't be deleted"
Merge "Add create_iscsi_target stub to TargetAdmin"
Merge "LVM: Activate source snap LV when cloning from volume"