Changes

=== Support sparse ghosts ===

=== Support sparse ghosts ===

'''Summary:''' While sparse ghost files were in part supported for quiet some time, we still was not able to handle big sparse ghost files and highly fragmented sparse ghost files.

'''Summary:''' While sparse ghost files were in part supported for quiet some time, we still was not able to handle big sparse ghost files and highly fragmented sparse ghost files effectively.

'''Merged:''' https://github.com/checkpoint-restore/criu/pull/1944 https://github.com/checkpoint-restore/criu/pull/1963

'''Merged:''' https://github.com/checkpoint-restore/criu/pull/1944 https://github.com/checkpoint-restore/criu/pull/1963