Migration tool

:Release Notes:
Add converter into single level db engine
it would start on before database and check db version for convert
In case db already "single level" - would do nothing

:Detailed Notes:
Add converter into single level db engine
it would start on before database and check db version for convert
In case db already "single level" - would do nothing

:Testing Performed:
Tested on TV with custom build

:Issues Addressed:
[BHV-7829] Migration tool approach №2

Open-webOS-DCO-1.0-Signed-off-by: Oleksandr Solomakha <oleksander.solomakha@lge.com>

Change-Id: I7848e396f581e4a528dd78ed6e93f699d53ee3ab
Reviewed-on: https://g2g.palm.com/5815
Reviewed-by: DCO Verification
Reviewed-by: Olexandr Solomakha <oleksander.solomakha@lge.com>
Tested-by: Olexandr Solomakha <oleksander.solomakha@lge.com>
Reviewed-by: Maksym Sditanov <maxim.sditanov@lge.com>
Reviewed-by: Oleg Yablokov <oleg.yablokov@lge.com>