This commit adds the functionality of checkpointing block index progress
and sync-ing (updating) the index during start of the block storage system

Change-Id: Ib1a325add455bce47e510ccfc7af052db51117e6
Signed-off-by: manish <manish.sethi@gmail.com>

This commit allows a block stream consumer read across multiple files.

Change-Id: I1bd053e8d022bf1daf01f61f9e3e1ae1629e334b
Signed-off-by: manish <manish.sethi@gmail.com>