Add Logical/Physical Block Size to the iSCSI Extent/LUN

Ticket:	#7176
(cherry picked from commit f3739dd34c43d1d56c3a542b326f7b4240898f41)
Remove iscsi_target_logical_blocksize field from the iSCSI Target

Ticket:	#7176
(cherry picked from commit 66873cc13e21e522c910f7d88f36a44766741c07)
Catch up block size changes in the backend

Ticket:	#7176
(cherry picked from commit 1b1a18ceef51ebbc62e3ec2ac438bbacede6a830)
Workaround South boolean bug

Ticket:	#7176
(cherry picked from commit 0aac16c9ed25eeb754b5e1c2fe6601479389d036)
Fix syntax error in ctl.conf generation

Ticket:	#7176
(cherry picked from commit ee77f56768575ef032e9f30e2cdb480f73ee619b)
Label block size field accordingly

Reported by:	mav
Ticket:	#7176

(cherry picked from commit 47bfc2338eede8aa531c2cc4e4ef425cee188150)