ART: Create a RemoveBlock method

The RemoveDeadBlocks should be separated into a utility function to remove
  a single block so that it can be used as a future utility method.

Change-Id: I4c67113fff24e92a66a81bc0e8edf9fbdda08cdf
Signed-off-by: Jean Christophe Beyler <jean.christophe.beyler@intel.com>