Change manila DB to have working unique constraint

Because Manila DB uses 'soft delete', we can't use
unique constaints properly. Solution is to change
'deleted' column from Boolean to the type of 'id'
column and write value of 'id' to 'delete'
on delete operation. To apply unique constr only
to not deleted records we will be adding
'deleted' column to every uc from now on.

Closes-Bug: #1272303
Change-Id: Ia673b91c7d7f700a25824766486a82f07203f3b6
Merge "Change manila DB to have working unique constraint"